Quantum computational complexity from quantum information to black holes and back

S Chapman, G Policastro - The European Physical Journal C, 2022 - Springer
Quantum computational complexity estimates the difficulty of constructing quantum states
from elementary operations, a problem of prime importance for quantum computation …

Real-and imaginary-time evolution with compressed quantum circuits

SH Lin, R Dilip, AG Green, A Smith, F Pollmann - PRX Quantum, 2021 - APS
The current generation of noisy intermediate-scale quantum computers introduces new
opportunities to study quantum many-body systems. In this paper, we show that quantum …

Quantum complexity and topological phases of matter

P Caputa, S Liu - Physical Review B, 2022 - APS
In this work, we find that the complexity of quantum many-body states, defined as a spread in
the Krylov basis, may serve as a probe that distinguishes topological phases of matter. We …

Decoherence, entanglement negativity, and circuit complexity for an open quantum system

A Bhattacharyya, T Hanif, SS Haque, A Paul - Physical Review D, 2023 - APS
In this paper, we compare the saturation timescales for complexity, linear entropy, and
entanglement negativity for two open quantum systems. Our first model is a coupled …

Complexity for conformal field theories in general dimensions

N Chagnet, S Chapman, J de Boer, C Zukowski - Physical review letters, 2022 - APS
We study circuit complexity for conformal field theory states in an arbitrary number of
dimensions. Our circuits start from a primary state and move along a unitary representation …

Time evolution of spread complexity and statistics of work done in quantum quenches

K Pal, K Pal, A Gill, T Sarkar - Physical Review B, 2023 - APS
We relate the probability distribution of the work done on a statistical system under a sudden
quench to the Lanczos coefficients corresponding to evolution under the postquench …

Spread complexity and topological transitions in the Kitaev chain

P Caputa, N Gupta, SS Haque, S Liu… - Journal of High Energy …, 2023 - Springer
A bstract A number of recent works have argued that quantum complexity, a well-known
concept in computer science that has re-emerged recently in the context of the physics of …

Krylov complexity and spectral form factor for noisy random matrix models

A Bhattacharyya, SS Haque, G Jafari… - Journal of High Energy …, 2023 - Springer
A bstract We study the spectral properties of two classes of random matrix models: non-
Gaussian RMT with quartic and sextic potentials, and RMT with Gaussian noise. We …

Quantum state complexity meets many-body scars

S Nandy, B Mukherjee, A Bhattacharyya… - Journal of Physics …, 2024 - iopscience.iop.org
Scar eigenstates in a many-body system refers to a small subset of non-thermal finite energy
density eigenstates embedded into an otherwise thermal spectrum. This novel non-thermal …

From CFTs to theories with Bondi-Metzner-Sachs symmetries: Complexity and out-of-time-ordered correlators

A Banerjee, A Bhattacharyya, P Drashni, S Pawar - Physical Review D, 2022 - APS
We probe the contraction from 2 d relativistic CFTs to theories with Bondi-Metzner-Sachs
(BMS) symmetries, or equivalently conformal Carroll symmetries, using diagnostics of …