Papers
Soft-Quantum Algorithms
Basil Kyriacou, Mo Kordzanganeh, Maniraman Periyasamy +1 more·Apr 7, 2026
Quantum operations on pure states can be fully represented by unitary matrices. Variational quantum circuits, also known as quantum neural networks, embed data and trainable parameters into gate-based operations and optimize the parameters via gradie...
One-to-one correspondence between Hierarchical Equations of Motion and Pseudomodes for Open Quantum System Dynamics
Kai Müller, Walter T. Strunz·Apr 7, 2026
We unite two of the most widely used approaches for strongly damped, non-Markovian open quantum dynamics, the Hierarchical Equations of Motion (HEOM) and the pseudomode method by proving two statements: First, every physical bath correlation function...
Quantum Fragmentation
Yiqiu Han, Oliver Hart, Alexey Khudorozhkov +1 more·Apr 7, 2026
We introduce a systematic protocol for constructing quantum Hilbert-space-fragmented Hamiltonians, whose Krylov-sector structure, unlike in classically fragmented models, can be fully resolved only in an entangled basis. The protocol takes as input a...
Higher rates for semi-device-independent randomness expansion by recycling input randomness
Rutvij Bhavsar, Hamid Tebyanian, Roger Colbeck·Apr 7, 2026
Although quantum random number generators rely on the inherent indeterminism of quantum mechanics, ensuring that the numbers produced are secure remains a significant challenge. We introduce two semi-device-independent randomness expansion protocols ...
Dissipative Hamilton Jacobi Dynamics and the Emergence of Quantum Wave Mechanics
Naleli Jubert Matjelo·Apr 7, 2026
We develop a dissipative extension of classical mechanics based on a complex, and more generally quaternionic, action principle that endows every classical system with an intrinsic environment. Decomposing the action into conservative and divergence-...
Agent Choice via Quantum Flux in Living Systems
R. E. Kastner·Apr 7, 2026
A basic model is provided that places active, intentional choices by biological organisms on a solid physical footing. The model is provisionally called "Agent Choice via Quantum Flux." It brings to bear specific physics on living systems in a way th...
Strong nonlocality with more imaginarity and less entanglement
Subrata Bera, Indranil Biswas, Atanu Bhunia +2 more·Apr 7, 2026
Complex numbers are central to the formulation of quantum mechanics, yet their role as a genuine resource is only beginning to be understood. In this work, we demonstrate that quantum states with intrinsically complex amplitudes provide a fundamental...
Directional and correlated optical emission from a waveguide-engineered molecule with local control
Clara Henke, Thomas Wilkens Sandø, Vasiliki Angelopoulou +10 more·Apr 7, 2026
Radiative coupling between quantum emitters leads to a range of spectacular emission phenomena. Dicke studied the foundations of collectively enhanced and suppressed decay, commonly referred to as super- and subradiance. Collective effects can furthe...
Probabilistic and approximate universal quantum purification machines
Zoe G. del Toro, Jessica Bavaresco·Apr 7, 2026
We study the task of lifting arbitrary quantum states and channels to purifications and Stinespring dilations, respectively, in both the probabilistic exact and deterministic approximate settings. We formalize this task through a general framework of...
Higher Nishimori Criticality and Exact Results at the Learning Transition of Deformed Toric Codes
Rushikesh A. Patil, Malte Pütz, Simon Trebst +2 more·Apr 7, 2026
We revisit a learning-induced tricritical point, at which three phases with strong, weak, and broken $Z_2$ symmetry meet, in the phase diagram of a deformed toric code wavefunction subjected to weak measurements. This setting is exactly dual to a cla...
Probing the Planck scale with quantum computation
Boaz Katz, Shlomi Kotler·Apr 7, 2026
General relativity and quantum mechanics are incompatible at the Planck scale. This contention can be examined if a quantum computer is set to operate at a rate that exceeds the classical limit of one operation per Planck volume-time, or equivalently...
Heterogeneous architectures enable a 138x reduction in physical qubit requirements for fault-tolerant quantum computing under detailed accounting
Pranav S. Mundada, Aleksei Khindanov, Yulun Wang +5 more·Apr 7, 2026
Quantum computer hardware is predicted to scale over hundreds of thousands of qubits coming online in the next decade. Despite significant theoretical and experimental QEC progress, quantum computer architecture has suffered a significant gap, with b...
Optimization of entanglement harvesting with arbitrary temporal profiles: the limit of second order perturbation theory
Marcos Morote-Balboa, T. Rick Perche·Apr 7, 2026
We study the protocol of entanglement harvesting when two local probes couple to the vacuum of a real scalar quantum field with arbitrary temporal profiles. We use a Hermite expansion to efficiently compute smeared field propagators in closed-form, r...
Error Correction in Lattice Quantum Electrodynamics with Quantum Reference Frames
Elias Rothlin, Carla Ferradini, Lin-Qing Chen·Apr 7, 2026
Is gauge symmetry merely a redundancy in our description, or does it carry a deeper information-theoretic significance? Quantum error-correcting codes (QECCs) show that redundancy can serve as a resource for protecting information against noise. In t...
From generating functions to the geometric Binder cumulant
Balázs Hetényi·Apr 7, 2026
We present an overview of the role of generating functions in quantum mechanical contexts, mainly in the modern theory of polarization and in the study of quantum phase transitions. Generating functions enable the derivation of moments and cumulants,...
Light-Induced Quantum Self-Trapping of Vibrational Excitons in an Optical Cavity
Vincent Pouthier, Saad Yalouz·Apr 7, 2026
In an optical cavity, strong light--matter coupling between excitons and photons has been widely reported as a way to enhance energy delocalization through spatially extended polaritonic states. In contrast, leveraging cavity-mediated light--matter e...
Shot-Based Quantum Encoding: A Data-Loading Paradigm for Quantum Neural Networks
Basil Kyriacou, Viktoria Patapovich, Maniraman Periyasamy +1 more·Apr 7, 2026
Efficient data loading remains a bottleneck for near-term quantum machine-learning. Existing schemes (angle, amplitude, and basis encoding) either underuse the exponential Hilbert-space capacity or require circuit depths that exceed the coherence bud...
QAFE$^2$: Quantum Accelerated Multiscale Finite Element Analysis
Yiren Wang, Michael Ortiz, Fehmi Cirak·Apr 7, 2026
The computational cost of concurrent multiscale finite element methods is dominated by the repeated solution of microscopic representative volume element (RVE) problems at macroscopic quadrature points. In this work, we introduce a quantum-classical ...
Necessary and sufficient conditions for the N-representability of functionals of the one-electron reduced density matrix
Jannis Erhard, Paul W. Ayers·Apr 7, 2026
We establish necessary and sufficient conditions for the N-representability of the universal one-electron reduced density matrix functional. Functionals satisfying these conditions are guaranteed to yield variational upper bounds on the true energy i...
Nonvariational quantum optimisation approaches to pangenome-guided sequence assembly
Josh Cudby, Sergii Strelchuk·Apr 7, 2026
Assembling genomes from short-read sequencing data remains difficult in repetitive regions, where reference bias and combinatorial complexity limit existing methods. Pangenome-guided sequence assembly (PGSA) mitigates reference bias by reconstructing...