Fast computational deep thermalization
- URL: http://arxiv.org/abs/2507.13670v1
- Date: Fri, 18 Jul 2025 05:42:05 GMT
- Title: Fast computational deep thermalization
- Authors: Shantanav Chakraborty, Soonwon Choi, Soumik Ghosh, Tudor Giurgică-Tiron,
- Abstract summary: Deep thermalization refers to the emergence of Haar-like randomness from quantum systems upon partial measurements.<n>We introduce computational deep thermalization and construct the fastest possible dynamics exhibiting it at infinite effective temperature.<n>Our results demonstrate a new form of computational thermalization, where thermal-like behavior arises from structured quantum states endowed with cryptographic properties.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Deep thermalization refers to the emergence of Haar-like randomness from quantum systems upon partial measurements. As a generalization of quantum thermalization, it is often associated with high complexity and entanglement. Here, we introduce computational deep thermalization and construct the fastest possible dynamics exhibiting it at infinite effective temperature. Our circuit dynamics produce quantum states with low entanglement in polylogarithmic depth that are indistinguishable from Haar random states to any computationally bounded observer. Importantly, the observer is allowed to request many copies of the same residual state obtained from partial projective measurements on the state -- this condition is beyond the standard settings of quantum pseudorandomness, but natural for deep thermalization. In cryptographic terms, these states are pseudorandom, pseudoentangled, and crucially, retain these properties under local measurements. Our results demonstrate a new form of computational thermalization, where thermal-like behavior arises from structured quantum states endowed with cryptographic properties, instead of from highly unstructured ensembles. The low resource complexity of preparing these states suggests scalable simulations of deep thermalization using quantum computers. Our work also motivates the study of computational quantum pseudorandomness beyond BQP observers.
Related papers
- Holographic deep thermalization for secure and efficient quantum random state generation [15.964002546782305]
We introduce holographic deep thermalization, a secure and hardware-efficient quantum random state generator.<n>By adopting a sequential application of a scrambling-measure-reset process, it trades space with time, and substantially reduces the required ancilla size.<n>Thanks to the resource reduction, our circuit-based implementation on IBM Quantum devices achieves genuine $5$-qubit random state generation utilizing only a total of $8$ qubits.
arXiv Detail & Related papers (2024-11-06T00:59:40Z) - Thermalization and Criticality on an Analog-Digital Quantum Simulator [133.58336306417294]
We present a quantum simulator comprising 69 superconducting qubits which supports both universal quantum gates and high-fidelity analog evolution.
We observe signatures of the classical Kosterlitz-Thouless phase transition, as well as strong deviations from Kibble-Zurek scaling predictions.
We digitally prepare the system in pairwise-entangled dimer states and image the transport of energy and vorticity during thermalization.
arXiv Detail & Related papers (2024-05-27T17:40:39Z) - Quantum computational advantage with constant-temperature Gibbs sampling [1.1930434318557157]
A quantum system coupled to a bath at some fixed, finite temperature converges to its Gibbs state.
This thermalization process defines a natural, physically-motivated model of quantum computation.
We consider sampling from the measurement outcome distribution of quantum Gibbs states at constant temperatures.
arXiv Detail & Related papers (2024-04-23T00:29:21Z) - Calculating the many-body density of states on a digital quantum
computer [58.720142291102135]
We implement a quantum algorithm to perform an estimation of the density of states on a digital quantum computer.
We use our algorithm to estimate the density of states of a non-integrable Hamiltonian on the Quantinuum H1-1 trapped ion chip for a controlled register of 18bits.
arXiv Detail & Related papers (2023-03-23T17:46:28Z) - Observation of partial and infinite-temperature thermalization induced
by repeated measurements on a quantum hardware [62.997667081978825]
We observe partial and infinite-temperature thermalization on a quantum superconducting processor.
We show that the convergence does not tend to a completely mixed (infinite-temperature) state, but to a block-diagonal state in the observable basis.
arXiv Detail & Related papers (2022-11-14T15:18:11Z) - Probing finite-temperature observables in quantum simulators of spin
systems with short-time dynamics [62.997667081978825]
We show how finite-temperature observables can be obtained with an algorithm motivated from the Jarzynski equality.
We show that a finite temperature phase transition in the long-range transverse field Ising model can be characterized in trapped ion quantum simulators.
arXiv Detail & Related papers (2022-06-03T18:00:02Z) - Preparing thermal states on noiseless and noisy programmable quantum
processors [0.0]
We provide two quantum algorithms with provable guarantees to prepare thermal states on near-term quantum computers.
The first algorithm is inspired by the natural thermalization process where the ancilla qubits act as the infinite thermal bath.
The second algorithm works for any system and in general runs in exponential time.
arXiv Detail & Related papers (2021-12-29T18:06:36Z) - Fast Thermalization from the Eigenstate Thermalization Hypothesis [69.68937033275746]
Eigenstate Thermalization Hypothesis (ETH) has played a major role in understanding thermodynamic phenomena in closed quantum systems.
This paper establishes a rigorous link between ETH and fast thermalization to the global Gibbs state.
Our results explain finite-time thermalization in chaotic open quantum systems.
arXiv Detail & Related papers (2021-12-14T18:48:31Z) - Universal quantum algorithmic cooling on a quantum computer [0.688204255655161]
We show how to universally and deterministically realize a general cooling procedure with shallow quantum circuits.
Our work paves the way for efficient and universal quantum algorithmic cooling with near-term as well as universal fault-tolerant quantum devices.
arXiv Detail & Related papers (2021-09-30T17:50:39Z) - Taking the temperature of a pure quantum state [55.41644538483948]
Temperature is a deceptively simple concept that still raises deep questions at the forefront of quantum physics research.
We propose a scheme to measure the temperature of such pure states through quantum interference.
arXiv Detail & Related papers (2021-03-30T18:18:37Z) - Testing a quantum annealer as a quantum thermal sampler [0.3437656066916039]
We study the diagonal thermal properties of the canonical one-dimensional transverse-field Ising model on a D-Wave 2000Q quantum annealing processor.
We find that the quantum processor fails to produce the correct expectation values predicted by Quantum Monte Carlo.
It remains an open question what thermal expectation values can be robustly estimated in general for arbitrary quantum many-body systems.
arXiv Detail & Related papers (2020-02-29T23:06:39Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.