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BEGIN:VEVENT
SUMMARY:Harpreet Arora (Caltech)
DTSTART;VALUE=DATE-TIME:20200529T180000Z
DTEND;VALUE=DATE-TIME:20200529T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/1
DESCRIPTION:Title: Investigating superconductivity in Twisted Bilayer Grap
hene (TBG)\nby Harpreet Arora (Caltech) as part of IQIM Seminar Series\n\n
\nAbstract\nWhile graphene has been dubbed as a ‘wonder material' becaus
e of amazing characteristics such as the ability to conduct electricity be
tter than copper and being two hundred times stronger than steel\, until r
ecently\, the key quantum phenomenon of superconductivity was missing from
the list of properties exhibited by graphene. In 2018\, an astonishing di
scovery showed that by placing two sheets of graphene on top of each other
which are rotationally misaligned by a small angle - in a structure known
as Twisted Bilayer Graphene (TBG)\, it is possible to realize superconduc
tivity when the rotation angle is close to the ‘Magic Angle' value of 1.
1 degrees$^{[1]}$. More surprisingly\, superconductivity in the initial re
ports was observed in close proximity to insulating states - resembling th
e phase diagram of High Tc superconductors. This sparked a fierce debate a
bout its origin and its possible relation to High Tc superconductors. In t
his talk\, I will show that by carefully engineering the dielectric enviro
nment of TBG\, it is possible to stabilize superconductivity in non-magic
angle TBG devices without the presence of any insulating states$^{[2]}$. T
his discovery imposes severe constraints on the origin of superconductivit
y in TBG. I will also discuss measurements providing direct evidence of sp
in-orbit coupling induced in TBG for the first time. I will conclude by ta
lking about possible experiments that will shed more light on the nature o
f superconductivity in TBG.\n\n\n[1] Cao et al. "Unconventional supercondu
ctivity in magic-angle graphene superlattices." Nature 556\, 43–50 (2018
).\n\n \n[2] Arora et al. "Superconductivity in metallic twisted bilayer g
raphene stabilized by WSe2" Nature (2020) In press. Preprint available at
https://arxiv.org/abs/2002.03003\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eugene Tang (Caltech)
DTSTART;VALUE=DATE-TIME:20200605T180000Z
DTEND;VALUE=DATE-TIME:20200605T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/2
DESCRIPTION:Title: The ghost in the radiation: Robust encodings of the bla
ck hole interior\nby Eugene Tang (Caltech) as part of IQIM Seminar Series\
n\n\nAbstract\nWe reconsider the black hole firewall puzzle\, emphasizing
that quantum error-correction\, computational complexity\, and pseudorando
mness are crucial concepts for understanding the black hole interior. We a
ssume that the Hawking radiation emitted by an old black hole is pseudoran
dom\, meaning that it cannot be distinguished from a perfectly thermal sta
te by any efficient quantum computation acting on the radiation alone. We
then infer the existence of a subspace of the radiation system which we in
terpret as an encoding of the black hole interior. This encoded interior i
s entangled with the late outgoing Hawking quanta emitted by the old black
hole\, and is inaccessible to computationally bounded observers who are o
utside the black hole. Specifically\, efficient operations acting on the r
adiation\, those with quantum computational complexity polynomial in the e
ntropy of the remaining black hole\, commute with a complete set of logica
l operators acting on the encoded interior\, up to corrections which are e
xponentially small in the entropy. Thus\, under our pseudorandomness assum
ption\, the black hole interior is well protected from exterior observers
as long as the remaining black hole is macroscopic.\n\nThe talk will be an
introductory version of my joint work with Isaac Kim and John Preskill\,
available at arxiv:2003.05451.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christina Knapp (Caltech)
DTSTART;VALUE=DATE-TIME:20200619T180000Z
DTEND;VALUE=DATE-TIME:20200619T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/4
DESCRIPTION:Title: Time-reversal-invariant topological superconductors and
the fractional Josephson effect\nby Christina Knapp (Caltech) as part of
IQIM Seminar Series\n\n\nAbstract\nTime-reversal-invariant topological sup
erconductor (TRITOPS) wires host Majorana-zero-mode Kramers pairs that hav
e been predicted to mediate a fractional Josephson effect. We explore the
fate of the TRITOPS fractional Josephson effect in the presence of local
time-dependent perturbations that instantaneously preserve time-reversal s
ymmetry. This talk will review why Majorana zero modes have attracted int
ense interest in both the condensed matter and quantum computing communiti
es. We will then focus on the Majorana-zero-mode Kramers pairs appearing
in TRITOPS wires. We consider a Josephson junction between two TRITOPS wi
res and demonstrate that the existence of a symmetry-protected ground stat
e degeneracy does not result in a robust adiabatic cycle.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sepehr Ghazi Nezami (Caltech)
DTSTART;VALUE=DATE-TIME:20200409T190000Z
DTEND;VALUE=DATE-TIME:20200409T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/5
DESCRIPTION:Title: Teleportation by size\, traversable wormholes\, and qua
ntum gravity in the lab\nby Sepehr Ghazi Nezami (Caltech) as part of IQIM
Seminar Series\n\n\nAbstract\nWith the long-term goal of studying quantum
gravity in the lab\, we propose holographic teleportation protocols that c
an be readily executed in table-top experiments. These protocols exhibit s
imilar behavior to that seen in recent traversable wormhole constructions:
information that is scrambled into one half of an entangled system will\,
following a weak coupling between the two halves\, unscramble into the ot
her half. We introduce the concept of "teleportation by size" to capture h
ow the physics of operator-size growth naturally leads to information tran
smission. The transmission of a signal through a semi-classical holographi
c wormhole corresponds to a rather special property of the operator-size d
istribution we call "size winding". For more general setups (which may not
have a clean emergent geometry)\, we argue that imperfect size winding is
a generalization of the traversable wormhole phenomenon. For example\, a
form of signalling continues to function at high temperature and at large
times for generic chaotic systems\, even though it does not correspond to
a signal going through a geometrical wormhole\, but rather to an interfere
nce effect involving macroscopically different emergent geometries. Finall
y\, we outline implementations feasible with current technology in two exp
erimental platforms: Rydberg atom arrays and trapped ions.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hsin-Yuan (Robert) Huang (Caltech)
DTSTART;VALUE=DATE-TIME:20200417T180000Z
DTEND;VALUE=DATE-TIME:20200417T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/6
DESCRIPTION:Title: Predicting Many Properties of a Quantum System from Ver
y Few Measurements\nby Hsin-Yuan (Robert) Huang (Caltech) as part of IQIM
Seminar Series\n\n\nAbstract\nPredicting properties of complex\, large-sca
le quantum systems is essential for developing quantum technologies. We pr
esent an efficient method for constructing an approximate classical descri
ption of a quantum state using very few measurements of the state. This de
scription\, called a classical shadow\, can be used to predict many differ
ent properties: order log(M) measurements suffice to accurately predict M
different functions of the state with high success probability. The number
of measurements is independent of the system size and saturates informati
on-theoretic lower bounds. Moreover\, target properties to predict can be
selected after the measurements are completed. We support our theoretical
findings with extensive numerical experiments. We apply classical shadows
to predict quantum fidelities\, entanglement entropies\, two-point correla
tion functions\, expectation values of local observables\, and the energy
variance of many-body local Hamiltonians. The numerical results highlight
the advantages of classical shadows relative to previously known methods.\
n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ding Zhong (Caltech)
DTSTART;VALUE=DATE-TIME:20200424T180000Z
DTEND;VALUE=DATE-TIME:20200424T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/7
DESCRIPTION:Title: Harvesting proximity effect in 2D Ferromagnetic Semicon
ductor Heterostructures for Spin and Valleytronics\nby Ding Zhong (Caltech
) as part of IQIM Seminar Series\n\n\nAbstract\nMonolayer transition metal
dichalcogenides host easily accessible spin and valley degrees of freedom
that can be used to encode and process information. With the advent of va
n der Waals heterostructures\, there are new opportunities to engineer spi
n and valleytronic devices with more advanced functionalities. In this tal
k\, I will describe a van der Waals heterostructure composed of a monolaye
r semiconductor\, WSe2\, and an ultrathin layered ferromagnetic semiconduc
tor\, CrI3. The integration of the two materials enables a strong magnetic
proximity effect in WSe2 and spin-selective charge transfer from WSe2 to
CrI3. By controlling the individual layer magnetization in CrI3 with a mag
netic field\, we show that the spin-dependent charge transfer between WSe2
and CrI3 is dominated by the interfacial CrI3 layer\, while the proximity
exchange field is highly sensitive to the layered magnetic structure as a
whole. These properties allow us to achieve unprecedented control of WSe2
valley properties in these devices. Moreover\, the photoluminescence dete
ction of WSe2 valley pseudospin provides us with a simple yet powerful too
l to probe the layer-resolved magnetization dynamics in CrI3.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ash Milsted (Caltech)
DTSTART;VALUE=DATE-TIME:20200508T180000Z
DTEND;VALUE=DATE-TIME:20200508T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/8
DESCRIPTION:Title: Simulating the collapse of false-vacuum bubbles in spin
chains\nby Ash Milsted (Caltech) as part of IQIM Seminar Series\n\n\nAbst
ract\nIt is possible that we live close to a local energetic minimum of th
e Standard Model\, with an ever-present chance of catastrophic decay to th
e true minimum. We study the real-time collapse of a small bubble of false
vacuum\, on a true-vacuum background\, in the vastly simpler setting of 1
+1-dimensional spin chains\, which nevertheless can capture key aspects if
the physics involved. We construct spatially localized false-vacuum bubbl
es using an infinite Matrix Product State ansatz and simulate their time e
volution\, demonstrating inelastic scattering when the walls of the bubble
s collide in an Ising-like chain. In contrast\, the simplest candidate mod
el -- the unmodified transverse-field Ising model with a small longitudina
l field -- is seen to exhibit only elastic scattering\, so that false-vacu
um bubbles merely bounce back after collapsing.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wilbur Shirley (Caltech)
DTSTART;VALUE=DATE-TIME:20200515T180000Z
DTEND;VALUE=DATE-TIME:20200515T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/9
DESCRIPTION:Title: Fractonic order\nby Wilbur Shirley (Caltech) as part of
IQIM Seminar Series\n\n\nAbstract\nIn recent years\, a theoretical new cl
ass of three-dimensional gapped phases of quantum matter has risen to the
fore. These phases\, originally discovered in the search for a self-correc
ting quantum memory\, are said to exhibit fractonic order --- a novel form
of long-range entanglement similar to intrinsic topological order\, but d
istinct from it due to a striking dependence of the universal properties o
f a phase on lattice geometry. This dependence manifests in a number of ex
otic features including fractional excitations with constrained mobility\,
unusually slow thermalization dynamics\, and ground state degeneracy that
grows with system size. In this talk\, I will give an introduction to the
topic\, and describe recent progress towards a systematic understanding o
f these phases in terms of emergent gauge theory and entanglement renormal
ization group flow.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Junyu Liu (Caltech)
DTSTART;VALUE=DATE-TIME:20201009T180000Z
DTEND;VALUE=DATE-TIME:20201009T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/10
DESCRIPTION:Title: Quantum computation and “cyberpunkian” quantum fiel
d theory\nby Junyu Liu (Caltech) as part of IQIM Seminar Series\n\n\nAbstr
act\nQuantum field theory is one of the greatest achievements by human bei
ngs in understanding the law of the universe. Almost all subjects in moder
n physics\, from condensed-matter physics to string theory\, are closely r
elated to the developments of quantum field theory. However\, Established
in the infinite-dimensional Hilbert spaces\, quantum field theory is very
hard to study\, especially when the theory is strongly coupled.\n\nThis ta
lk is a summary of quantum opportunities for solving quantum field theory
theoretically and numerically\, based on a series of works by the speaker
and collaborators. Specifically\, we describe a digital quantum simulation
algorithm for simulating domain wall scatterings in the 1+1 dimensional q
uantum field theory\, which could be regarded as a toy version of cosmolog
ical false vacuum decay in the real universe\, as an example. We will disc
uss some potential fundamental limitations of classical algorithms\, how q
uantum computers will help us solve the problem\, and how good quantum com
puters are (the quantum-extended Church-Turing Thesis). Moreover\, we will
discuss some great classical algorithms developed in recent years. Namely
\, matrix product states in quantum many-body systems (tensor networks) an
d semidefinite programming in conformal field theories (the conformal boot
strap).\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yingfei Gu (Caltech)
DTSTART;VALUE=DATE-TIME:20201016T180000Z
DTEND;VALUE=DATE-TIME:20201016T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/11
DESCRIPTION:Title: Scrambling and Branching\nby Yingfei Gu (Caltech) as pa
rt of IQIM Seminar Series\n\n\nAbstract\nOut-of-time-order correlators (OT
OCs) describe quantum chaos in a way comparable to classical chaos\, at le
ast for systems with a large parameter N\, where the early-time OTOCs are
characterized by a Lyapunov exponent\, whose inverse defines a time scale
known as Lyapunov time. In this talk\, I will discuss another time scale c
alled branching time and derive a bound on it for SYK-like models. It turn
s out that the branching time plays significantly different roles in the s
trong and weak coupling limits\, suggesting two different mechanisms for s
crambling. This talk is based on [1812.00120] with Alexei Kitaev and work
in progress with Alexei Kitaev and Pengfei Zhang.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cyprian Lewandowski (Caltech)
DTSTART;VALUE=DATE-TIME:20201023T180000Z
DTEND;VALUE=DATE-TIME:20201023T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/12
DESCRIPTION:Title: Pairing in magic-angle twisted bilayer graphene: role o
f phonon and plasmon umklapp\nby Cyprian Lewandowski (Caltech) as part of
IQIM Seminar Series\n\n\nAbstract\nIdentifying the microscopic mechanism f
or superconductivity in magic-angle twisted bilayer graphene (MATBG) is an
outstanding open problem. While MATBG exhibits a rich phase-diagram\, dri
ven partly by the strong interactions relative to the electronic bandwidth
\, its single-particle properties are unique and likely play an important
role in some of the phenomenological complexity. Some of the salient featu
res include an electronic bandwidth smaller than the characteristic phonon
bandwidth and a non-trivial structure of the underlying Bloch wavefunctio
ns. In this talk\, I will discuss a theoretical study of the cooperative e
ffects due to phonons and plasmons on pairing in order to disentangle the
distinct role played by these modes on superconductivity. We will consider
a variant of MATBG with an enlarged number of fermion flavors\, N≫1\, w
here the study of pairing instabilities reduces to the conventional (weak-
coupling) Eliashberg framework. In particular\, I will show that certain u
mklapp processes involving mini-optical phonon modes\, which arise physica
lly as a result of the folding of the original acoustic branch of graphene
due to the moiré superlattice structure\, contribute significantly towar
ds enhancing pairing. Time permitting\, I will also consider the role play
ed by the dynamics of the screened Coulomb interaction on pairing\, which
leads to an enhancement in a narrow window of fillings\, and study the eff
ect of external screening due to a metallic gate on superconductivity. Fin
ally\, I will propose a smoking-gun experiment to detect resonant features
associated with the phonon-umklapp processes in the differential conducta
nce and also discuss several experimental implications of a pairing mechan
isms relying on plasmons.\n\nThe talk will follow a joint work with Debanj
an Chowdhury and Jonathan Ruhman\, available at arXiv:2007.15002\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yuan Su (Caltech)
DTSTART;VALUE=DATE-TIME:20201030T180000Z
DTEND;VALUE=DATE-TIME:20201030T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/13
DESCRIPTION:Title: A Theory of Trotter Error\nby Yuan Su (Caltech) as part
of IQIM Seminar Series\n\n\nAbstract\nWe develop a theory of Trotter erro
r that overcomes the limitations of prior approaches based on truncating t
he Baker-Campbell-Hausdorff expansion. Our analysis directly exploits the
commutativity of operator summands\, producing tighter error bounds for bo
th real- and imaginary-time evolutions. Whereas previous work achieves sim
ilar goals for systems with Lie-algebraic structure or certain low-order f
ormulas\, our approach holds in general.\nWe give a host of improved algor
ithms for digital quantum simulation and quantum Monte Carlo methods\, inc
luding simulations of nearest-neighbor lattice Hamiltonians\, second-quant
ized plane-wave electronic structure\, $k$-local Hamiltonians\, rapidly de
caying power-law interactions\, clustered Hamiltonians\, the transverse fi
eld Ising model\, and quantum ferromagnets\, nearly matching or even outpe
rforming the best previous results.\nWe obtain further speedups using the
fact that product formulas can preserve the locality of the simulated syst
em. Specifically\, we show that local observables can be simulated with co
mplexity independent of the system size for power-law interacting systems\
, which implies a Lieb-Robinson bound as a byproduct.\nOur analysis reprod
uces known tight bounds for first- and second-order formulas. Our higher-o
rder bound overestimates the complexity of simulating a one-dimensional He
isenberg model with an even-odd ordering of terms by only a factor of 5\,
and is close to tight for power-law interactions and other orderings of te
rms. This suggests that our theory can accurately characterize Trotter err
or in terms of both asymptotic scaling and constant prefactor.\n\nBased on
arXiv:1901.00564 and arXiv:1912.08854.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chaitali Joshi (Caltech)
DTSTART;VALUE=DATE-TIME:20201106T190000Z
DTEND;VALUE=DATE-TIME:20201106T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/14
DESCRIPTION:Title: Quantum photonics with color qubits\nby Chaitali Joshi
(Caltech) as part of IQIM Seminar Series\n\n\nAbstract\nOptical photons ar
e excellent flying qubits for long-distance quantum networks due to neglig
ible thermal noise and decoherence at room temperature. In this talk\, I w
ill discuss how frequency encoding can be combined with nonlinear optics a
nd fiber and integrated photonic technologies to address challenges in sca
ling future photonic quantum networks. Frequency multiplexing has had a pr
ofound impact on classical telecommunication networks\, creating low loss
and inexpensive hardware that can be exploited for quantum applications. I
will describe quantum photonic applications where frequency encoding prov
ides a distinct advantage in terms of scaling losses and resource overhead
compared to polarization\, spatial or temporal mode encoding. \n\nCoheren
t manipulation of light in the frequency domain at the single-photon level
requires a strong\, noise-free nonlinear process. I will discuss our impl
ementation of four-wave mixing (FWM) in a commercial dispersion-shifted fi
ber to achieve quantum frequency conversion with near-unity efficiency and
low noise. I will discuss how we used this process as an active "frequenc
y switch" to realize a low-loss multiplexed single-photon source that can
be scaled to the deterministic regime. Next\, I will discuss how we used t
his process as a frequency beam-splitter to demonstrate two-photon Hong-Ou
-Mandel type interference between entangled photons of different colors- a
hallmark of quantum indistinguishability. Finally\, I will discuss our re
alization of a FWM-based "time lens" for the generation and detection of s
ingle-photon waveforms with picosecond resolution. \n\nBased on Joshi et
al.\, Nat. Comm. 9\, 847 (2018)\, Joshi et al. Phys. Rev. Lett. 124\, 1436
01(2020)\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chi Fang (Anthony) Chen (Caltech)
DTSTART;VALUE=DATE-TIME:20201113T190000Z
DTEND;VALUE=DATE-TIME:20201113T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/15
DESCRIPTION:Title: Hierarchy of light cones in power-law interacting syste
ms: review of recent bounds and saturating protocols\nby Chi Fang (Anthony
) Chen (Caltech) as part of IQIM Seminar Series\n\n\nAbstract\nIn quantum
many-body systems with local interactions\, quantum information and entang
lement cannot spread outside of a linear light cone\, which expands at an
emergent velocity analogous to the speed of light. Though\, realistic syst
ems often have a power-law interaction $1/r^α$. In this talk\, we discuss
a hierarchy of light cones in these long-ranged systems: At the same α\,
some quantum information processing tasks are constrained by a `linear’
light cone\, while others are not. In one spatial dimension\, a linear li
ght cone exists for every many-body state when α > 3 (Lieb-Robinson light
cone)\; for a typical state chosen uniformly at random when α > 5/2 (Fro
benius light cone)\; and for every state of a noninteracting system when
α > 2 (free light cone). These bounds apply to time-dependent systems and
are saturated by explicit protocols. Some of these linear light cones ext
end to algebraic ones and/or generalize to higher dimensions. As an examp
le among the various implications\, universal quantum state transfer\, as
well as many-body quantum chaos\, is bounded by the Frobenius light cone a
nd\, therefore\, is poorly constrained by all Lieb-Robinson bounds. This t
alk will be an up-to-date review over regimes of α\, recent protocols and
the key physical intuitions and the high-level proof ideas.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:TBA
DTSTART;VALUE=DATE-TIME:20201120T190000Z
DTEND;VALUE=DATE-TIME:20201120T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/16
DESCRIPTION:by TBA as part of IQIM Seminar Series\n\nAbstract: TBA\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Xin Xie (Caltech)
DTSTART;VALUE=DATE-TIME:20201204T190000Z
DTEND;VALUE=DATE-TIME:20201204T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/17
DESCRIPTION:Title: Precise Calibrations of Few-Body Physics in Potassium-3
9\nby Xin Xie (Caltech) as part of IQIM Seminar Series\n\nInteractive live
stream: https://caltech.zoom.us/j/97280252054\n\nAbstract\nWe perform prec
ise studies of two-and three-body interactions near an intermediate-streng
th Feshbach resonance in potassium-39 at 33.5820(14) G. Precise measuremen
t of dimer binding energies enables the construction of a complete two-bod
y coupled-channel model for determination of the scattering lengths with a
n unprecedented low uncertainty. Utilizing such an accurate scattering len
gth map\, we unambiguously locate four distinct features in the Efimov thr
ee-body structure. Meticulous characterization of and correction for finit
e temperature effects ensure high accuracy on the measurements of these fe
atures at large-magnitude scattering lengths. We report the ground Efimov
resonance location to be at −14.05(17) times the van der Waals length r_
vdW\, significantly deviating from the value of −9.7r_vdW predicted by v
an der Waals universality [1]. While three of these features form ratios t
hat obey the Efimov universal scaling to within 10% [2].\n\n[1] https://jo
urnals.aps.org/prl/abstract/10.1103/PhysRevLett.123.233402\n[2] https://jo
urnals.aps.org/prl/accepted/94071Yb5H8819f8421972b1289f4d229daf32da51\n
URL:https://caltech.zoom.us/j/97280252054
END:VEVENT
BEGIN:VEVENT
SUMMARY:TBA
DTSTART;VALUE=DATE-TIME:20201211T190000Z
DTEND;VALUE=DATE-TIME:20201211T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/18
DESCRIPTION:by TBA as part of IQIM Seminar Series\n\nInteractive livestrea
m: https://caltech.zoom.us/j/97280252054\nAbstract: TBA\n
URL:https://caltech.zoom.us/j/97280252054
END:VEVENT
BEGIN:VEVENT
SUMMARY:TBA
DTSTART;VALUE=DATE-TIME:20201218T190000Z
DTEND;VALUE=DATE-TIME:20201218T200000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/19
DESCRIPTION:by TBA as part of IQIM Seminar Series\n\nInteractive livestrea
m: https://caltech.zoom.us/j/97280252054\nAbstract: TBA\n
URL:https://caltech.zoom.us/j/97280252054
END:VEVENT
BEGIN:VEVENT
SUMMARY:Harry Levine (Harvard)
DTSTART;VALUE=DATE-TIME:20201028T180000Z
DTEND;VALUE=DATE-TIME:20201028T190000Z
DTSTAMP;VALUE=DATE-TIME:20201204T170220Z
UID:IQIM-seminar/20
DESCRIPTION:Title: Quantum simulation and quantum computation with program
mable Rydberg atom arrays\nby Harry Levine (Harvard) as part of IQIM Semin
ar Series\n\n\nAbstract\nNeutral atom arrays form a powerful platform for
studying and coherently controlling many-body quantum systems. These array
s can be readily scaled to hundreds of individually controlled atoms with
flexible\, programmable geometries. Strong atomic interactions can be intr
oduced by coherent excitation to Rydberg states\, resulting in a rich spin
Hamiltonian with variable interaction range\, as well as tools for quantu
m information processing. In this talk\, I will discuss two applications o
f coherent control over 1D atom arrays to create and benchmark entangled s
tates. In the first\, we utilize the Rydberg Hamiltonian to globally drive
a 20 atom array into a fully entangled Schrödinger cat state. In the sec
ond\, we introduce a new protocol for a universal two-qubit gate on neutra
l atoms\, and demonstrate its parallel implementation on several pairs of
qubits. Finally\, I will discuss our ongoing work scaling our system to 2D
arrays of hundreds of qubits\, including preliminary results exploring th
e phase diagram of 2D arrays as well as applications to graph theory optim
ization problems.\n
END:VEVENT
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