108 citations · 130 across the 10 of their papers we have counts for
10 papers
Collective advantage from a minimal record in a quantum information engine
Kangqiao Liu, Jie Gu, Deyou Chen
For a single particle, a quantum information engine can turn measurement fluctuations into transport by raising a barrier behind the particle each time its position is measured. Wh…
Maximal-velocity deficit under a finite-support constraint in a hard-wall half-line continuous-time quantum walk
Kangqiao Liu, Deyou Chen
Continuous-time quantum walks on a lattice spread ballistically and converge to a limiting distribution for the rescaled position. On the hard-wall half line the boundary reflects…
Classical codes violate the conjectured square-root bound for quantum random access codes
Kangqiao Liu
We consider whether every quantum random access code (QRAC) with density-operator encodings and arbitrary decoding measurements obeys the conjectured bound ,…
Chaos bound for spinning particles in Kerr-Newman-AdS black holes
Deyou Chen, Chuang Yang, Kangqiao Liu
In this paper, we investigate the chaos bound violation of spinning charged test particles in the Kerr--Newman--AdS spacetime by comparing the Lyapunov exponent of unstable circula…
Finite-frequency fluctuation-response bounds for open quantum systems
Jie Gu, Kangqiao Liu
We derive a finite-frequency fluctuation-response inequality for Markovian open quantum systems in an input-output setting. For any downstream measurement of the emitted field, the…
Response kinetic uncertainty relation for Markovian open quantum systems
Kangqiao Liu, Jie Gu
Response uncertainty relations in stochastic thermodynamics extend precision bounds to the sensitivity of observables under external perturbations. Here we derive a quantum respons…
Dynamical activity universally bounds precision of response in Markovian nonequilibrium systems
Kangqiao Liu, Jie Gu
The exploration of far-from-equilibrium systems has been at the forefront of nonequilibrium thermodynamics, with a particular focus on understanding the fluctuations and response o…
Maxwell's demon for quantum transport
Kangqiao Liu, Masaya Nakagawa, Masahito Ueda
While most of the existing quantum information engines assisted by Maxwell's demon harness thermal fluctuations, those that rectify only quantum fluctuations have recently been con…
Power-law escape rate of SGD
Takashi Mori, Liu Ziyin, Kangqiao Liu +1
Stochastic gradient descent (SGD) undergoes complicated multiplicative noise for the mean-square loss. We use this property of SGD noise to derive a stochastic differential equatio…
Thermodynamic Uncertainty Relation for Arbitrary Initial States
Kangqiao Liu, Zongping Gong, Masahito Ueda
The thermodynamic uncertainty relation (TUR) describes a trade-off relation between nonequilibrium currents and entropy production and serves as a fundamental principle of nonequil…