373 citations · 1.1k across the 27 of their papers we have counts for
28 papers
BARC codes: general polynomial framework for coherent-state superposition codes
Praneel Gore, Davit Aghamalyan, Varun Narasimhachar +1
We introduce an algebraic framework for constructing a new class of quantum error-correcting codes, bosonic algebraically-restricted constellation (BARC) codes. The code states are…
Time-ordered free energy in correlated quantum systems: An agentic approach
Ruo Cheng Huang, Isha Singh Le Xue, Yuxuan Qu +3
How much work can an agent extract from a temporal sequence of quantum states when it can only operate online under causal constraints---deciding which energy extraction method to…
Approximate virtual quantum broadcasting
Matthew Simon Tan, Davit Aghamalyan, Varun Narasimhachar
The no-broadcasting theorem, a fundamental limitation on the communication of quantum information, holds that a physical process cannot broadcast copies of an unknown quantum state…
The Dirac--Bergmann approach to optimal control theory
Davit Aghamalyan, Aleek Maity, Varun Narasimhachar +1
We present a novel framework for optimal control in both classical and quantum systems. Our approach leverages the Dirac--Bergmann algorithm: a systematic method for formulating an…
Optimized circuits for windowed modular arithmetic with applications to quantum attacks against RSA
Alessandro Luongo, Varun Narasimhachar, Adithya Sireesh
Windowed arithmetic [Gidney, 2019] is a technique for reducing the cost of quantum arithmetic circuits with space--time tradeoffs using memory queries to precomputed tables. It can…
Measurement-based uncomputation of quantum circuits for modular arithmetic
Alessandro Luongo, Antonio Michele Miti, Varun Narasimhachar +1
Measurement-based uncomputation (MBU) is a technique used to perform probabilistic uncomputation of quantum circuits. We formalize this technique for the case of single-qubit regis…
Amplification, Mitigation and Energy Storage via Constrained Thermalization
Harshank Shrotriya, Midhun Krishna, Leong-Chuan Kwek +2
Amplification (mitigation) is the increase (decrease) in the change of thermodynamic quantities when an initial thermal state is thermalized to a different temperature in the prese…
The coherent measurement cost of coherence distillation
Varun Narasimhachar
Quantum coherence -- an indispensable resource for quantum technologies -- is known to be distillable from a noisy form using operations that cannot create it. However, distillatio…
Causal classification of spatiotemporal quantum correlations
Minjeong Song, Varun Narasimhachar, Bartosz Regula +2
From correlations in measurement outcomes alone, can two otherwise isolated parties establish whether such correlations are atemporal? That is, can they rule out that they have bee…
Quantum-optimal information encoding using noisy passive linear optics
Andrew Tanggara, Ranjith Nair, Syed Assad +5
The amount of information that a noisy channel can transmit has been one of the primary subjects of interest in information theory. In this work we consider a practically-motivated…
Engines for predictive work extraction from memoryful quantum stochastic processes
Ruo Cheng Huang, Paul M. Riechers, Mile Gu +1
Quantum information-processing techniques enable work extraction from a system's inherently quantum features, in addition to the classical free energy it contains. Meanwhile, the s…
Fisher information universally identifies quantum resources
Kok Chuan Tan, Varun Narasimhachar, Bartosz Regula
We show that both the classical as well as the quantum definitions of the Fisher information faithfully identify resourceful quantum states in general quantum resource theories, in…
Agents governed by quantum mechanics can use it intersubjectively and consistently
Varun Narasimhachar
Following Frauchiger and Renner's discovery of a conflict between quantum mechanics and certain commonsense reasoning axioms, much work has gone into finding alternative axiomatiza…
Thermodynamic resources in continuous-variable quantum systems
Varun Narasimhachar, Syed Assad, Felix C. Binder +3
Thermodynamic resources, beyond their well-known usefulness in work extraction and other thermodynamic tasks, are often important also in tasks that are not evidently thermodynamic…
Coherence manipulation with dephasing-covariant operations
Bartosz Regula, Varun Narasimhachar, Francesco Buscemi +1
We characterize the operational capabilities of quantum channels which can neither create nor detect quantum coherence vis-à-vis efficiently manipulating coherence as a resource. W…
Understanding quantum physics through simple experiments: from wave-particle duality to Bell's theorem
Ish Dhand, Adam D'Souza, Varun Narasimhachar +5
Quantum physics, which describes the strange behavior of light and matter at the smallest scales, is one of the most successful descriptions of reality, yet it is notoriously inacc…
Quantifying memory capacity as a quantum thermodynamic resource
Varun Narasimhachar, Jayne Thompson, Jiajun Ma +2
The information-carrying capacity of a memory is known to be a thermodynamic resource facilitating the conversion of heat to work. Szilard's engine explicates this connection throu…
Operational resource theory of continuous-variable nonclassicality
Benjamin Yadin, Felix C. Binder, Jayne Thompson +3
Genuinely quantum states of a harmonic oscillator may be distinguished from their classical counterparts by the Glauber-Sudarshan P-representation -- a state lacking a positive P-f…
Matrix Product States for Quantum Stochastic Modelling
Chengran Yang, Felix C. Binder, Varun Narasimhachar +1
In stochastic modeling, there has been a significant effort towards finding predictive models that predict a stochastic process' future using minimal information from its past. Mea…
The resource theory under conditioned thermal operations
Varun Narasimhachar, Gilad Gour
The "thermal operations" framework developed in past works is used to model the evolution of microscopic quantum systems in contact with thermal baths. Here we extend this model to…
The Conditional Uncertainty Principle
Gilad Gour, Andrzej Grudka, Michał Horodecki +3
We develop a general operational framework that formalizes the concept of conditional uncertainty in a measure-independent fashion. Our formalism is built upon a mathematical relat…
Uncertainty, joint uncertainty, and the quantum uncertainty principle
Varun Narasimhachar, Alireza Poostindouz, Gilad Gour
Historically, the element of uncertainty in quantum mechanics has been expressed through mathematical identities called uncertainty relations, a great many of which continue to be…
Low-temperature thermodynamics with quantum coherence
Varun Narasimhachar, Gilad Gour
Thermal operations are an operational model of non-equilibrium quantum thermodynamics. In the absence of coherence between energy levels, exact state transition conditions under th…
Quantumness of correlations, quantumness of ensembles and quantum data hiding
Marco Piani, Varun Narasimhachar, John Calsamiglia
We study the quantumness of correlations for ensembles of bi- and multi-partite systems and relate it to the task of quantum data hiding. Quantumness is here intended in the sense…