As with any quantum computing platform, semiconductor quantum dot devices

require sophisticated hardware and controls for operation. The increasing

complexity of quantum dot devices necessitates the advancement of automated

control software and image recognition techniques for rapidly evaluating charge

stability diagrams. We use an image analysis toolbox developed in Python to

automate the calibration of virtual gates, a process that previously involved a

large amount of user intervention. Moreover, we show that straightforward

# All

We propose a practical protocol to generate and observe a non-Abelian

geometric phase using a periodically driven Raman process in the hyperfne

ground state manifold of atoms in a dilute ultracold gas. Our analysis is based

upon recent developments and application of Floquet theory to periodically

driven quantum systems. The simulation results show the non-Abelian gauge

transformation and the non-commuting property of the SU(2) transformation

operators. Based on these results, we propose a possible experimental

We present a $2\mathrm{-dimensional}$ quantum walker on curved discrete

surfaces with dynamical geometry. This walker extends the quantum walker over

the fixed triangular lattice introduced in

\cite{quantum_walk_triangular_lattice}. We write the discrete equations of the

walker on an arbitrary triangulation, whose flat spacetime limit recovers the

Dirac equation in (2+1)-dimension. The geometry is changed through Pachner

moves, allowing the surface to transform into any topologically equivalent

Universal properties of a critical quantum spin chain are encoded in the

underlying conformal field theory (CFT). This underlying CFT is fully

characterized by its conformal data. We propose a method to extract the

conformal data from a critical quantum spin chain with both periodic and

anti-periodic boundary conditions (PBC and APBC) based on low-energy

eigenstates, generalizing previous work on spin chains with only PBC. First,

scaling dimensions and conformal spins are extracted from the energies and

We introduce quantum circuits in two and three spatial dimensions which are

classically simulable, despite producing a high degree of operator

entanglement. We provide a partial characterization of these "automaton"

quantum circuits, and use them to study operator growth, information spreading,

and local charge relaxation in quantum dynamics with subsystem symmetries,

which we define as overlapping symmetries that act on lower-dimensional

submanifolds. With these symmetries, we discover the anomalous subdiffusion of

A powerful tool for studying the behavior of classical field theories is

Derrick's theorem: one may rule out the existence of localized inhomogeneous

stable field configurations (solitons) by inspecting the Hamiltonian and making

scaling arguments. For example, the theorem can be used to rule out compact

domain wall configurations for the classic $\phi^4$ theory in $3+1$ dimensions

and greater. We argue no such obstruction to constructing solitons exists in

One of the stunning consequences of quantum correlations in thermodynamics is

the reversal of the arrow of time, recently shown experimentally in [K.

Micadei, et al., Nat. Commun. 10:2456 (2019)], and manifesting itself by a

reversal of the heat flow (from the cold system to the hot one). Here, we show

that contrary to what could have been expected, heat flow reversal can happen

without reversal of the arrow of time. Moreover, contrasting with previous

Consider a classical system, which is in the state described by probability

distribution $p$ or $q$, and embed these classical informations into quantum

system by a physical map $\Gamma$, $\rho=\Gamma(p)$ and $\sigma=\Gamma(q)$.

Intuitively, the pair $\{p_{\rho}^{M},p_{\sigma}^{M}\}$ of the distributions of

the data of the measurement $M$ on the pair $\{\rho,\sigma\}$ should contain

strictly less information than the pair $\{p,q\}$ provided the pair

$\{\rho,\sigma\}$ is non-commutative. Indeed, this statement had been shown if

Author(s): Jia-Qi Zhou, Ling Cai, Qi-Ping Su, and Chui-Ping Yang

Implementation of a discrete-time quantum walk (DTQW) with superconducting qubits is difficult since on-chip superconducting qubits cannot hop between lattice sites. We propose an efficient protocol for the implementation of DTQW in circuit quantum electrodynamics (QED), in which only $N+1$ qutrits,...

[Phys. Rev. A 100, 012343] Published Thu Jul 25, 2019

- Read more about Protocol of a quantum walk in circuit QED
- Log in or register to post comments

Author(s): Yafei Wen, Pai Zhou, Zhongxiao Xu, Liang Yuan, Haoyi Zhang, Shengzhi Wang, Long Tian, Shujing Li, and Hai Wang

A source that can generate atom-photon quantum correlations or entanglement based on a quantum memory is a basic building block of quantum repeaters (QRs). To achieve high entanglement generation rates in ensemble-based QRs, spatial-, temporal-, and spectral-multimode memories are needed. Previous t...

[Phys. Rev. A 100, 012342] Published Thu Jul 25, 2019