25 citations · 205 across the 29 of their papers we have counts for
30 papers
Hybrid nonlocality via atom photon interactions with and without impurities
Pritam Halder, Ratul Banerjee, Saptarshi Roy +1
To obtain Bell statistics from hybrid systems composed of finite- and infinite-dimensional systems, we propose a hybrid measurement scheme, in which the continuous mode is measured…
Understanding Best Subset Selection: A Tale of Two C(omplex)ities
Saptarshi Roy, Ambuj Tewari, Ziwei Zhu
We consider the problem of best subset selection (BSS) under high-dimensional sparse linear regression model. Recently, Guo et al. (2020) showed that the model selection performanc…
Thompson Sampling for High-Dimensional Sparse Linear Contextual Bandits
Sunrit Chakraborty, Saptarshi Roy, Ambuj Tewari
We consider the stochastic linear contextual bandit problem with high-dimensional features. We analyze the Thompson sampling algorithm using special classes of sparsity-inducing pr…
Quantum networks boosted by entanglement with a control system
Tamal Guha, Saptarshi Roy, Giulio Chiribella
Networks of quantum devices with coherent control over their configuration offer promising advantages in quantum information processing. So far, the investigation of these advantag…
How does overparametrization affect performance on minority groups?
Subha Maity, Saptarshi Roy, Songkai Xue +2
The benefits of overparameterization for the overall performance of modern machine learning (ML) models are well known. However, the effect of overparameterization at a more granul…
Quantum Dense Coding Network using Multimode Squeezed States of Light
Ayan Patra, Rivu Gupta, Saptarshi Roy +2
We present a framework of a multimode dense coding network with multiple senders and a single receiver using continuous variable systems. The protocol is scalable to arbitrary numb…
Significance of Fidelity Deviation in Continuous Variable Teleportation
Ayan Patra, Rivu Gupta, Saptarshi Roy +1
Performance of quantum teleportation is typically measured by the average fidelity, an overlap between the input and output states. Along with the first moment, we introduce the se…
High-dimensional variable selection with heterogeneous signals: A precise asymptotic perspective
Saptarshi Roy, Ambuj Tewari, Ziwei Zhu
We study the problem of exact support recovery for high-dimensional sparse linear regression under independent Gaussian design when the signals are weak, rare, and possibly heterog…
Quantum illumination with a light absorbing target
Rivu Gupta, Saptarshi Roy, Tamoghna Das +1
In a quantum illumination (QI) protocol, the task is to detect the presence of the target which is typically modelled by a partially reflecting beam splitter. We analyze the perfor…
Quantum illumination with noisy probes: Conditional advantages of non-Gaussianity
Rivu Gupta, Saptarshi Roy, Tamoghna Das +1
Entangled states, like the two-mode squeezed vacuum state, are known to give quantum advantage in the illumination protocol, a method to detect a weakly reflecting target submerged…
Localizing genuine multimode entanglement: Asymmetric gains via non-Gaussianity
Ratul Banerjee, Saptarshi Roy, Tamoghna Das +1
Measurement-based quantum correlation mimics several characteristics of multipartite quantum correlations and at the same time, it reduces the parent system to a smaller subsystem.…
Emergence of Monogamy under Static and Dynamic Scenarios
Rivu Gupta, Saptarshi Roy, Shiladitya Mal +1
Characterizing multipartite quantum correlations beyond two parties is of utmost importance for building cutting edge quantum technologies, although the comprehensive picture is st…
Robustness of Higher Dimensional Nonlocality against dual noise and sequential measurements
Saptarshi Roy, Asmita Kumari, Shiladitya Mal +1
Robustness in the violation of Collins-Linden-Gisin-Masser-Popescu (CGLMP) inequality is investigated from the dual perspective of noise in measurements as well as in states. To qu…
Gain in Performance of Teleportation with Uniformity-breaking Distributions
Saptarshi Roy, Shiladitya Mal, Aditi Sen De
Prior information about the input state can be utilized to enhance the efficiency of quantum teleportation which we quantify using the first two moments of fidelity. The input know…
Restrictions on shareability of classical correlations for random multipartite quantum states
Saptarshi Roy, Shiladitya Mal, Aditi Sen De
Unlike quantum correlations, the shareability of classical correlations (CCs) between two-parties of a multipartite state is assumed to be free since there exist states for which C…
Distribution of entanglement with variable range interactions
Leela Ganesh Chandra Lakkaraju, Srijon Ghosh, Saptarshi Roy +1
Distribution of quantum entanglement is investigated for an anisotropic quantum XY model with variable range interactions and in the presence of a uniform transverse magnetic field…
Rating the performance of noisy teleportation using fluctuations in fidelity
Saptarshi Roy, Arkaprabha Ghosal
Quantum teleportation is one of the most pioneering features of the quantum world. Typically, the quality of a teleportation protocol is solely judged by its average fidelity. In t…
Computable genuine multimode entanglement measure: Gaussian vs. non-Gaussian
Saptarshi Roy, Tamoghna Das, Aditi Sen De
Genuine multimode entanglement in continuous variable systems can be quantified by exploring the geometry of the state-space, namely via the generalized geometric measure (GGM) whi…
Density Power Downweighting and Robust Inference: Some New Strategies
Saptarshi Roy, Kaustav Chakraborty, Somnath Bhadra +1
Preserving the robustness of the procedure has, at the present time, become almost a default requirement for statistical data analysis. Since efficiency at the model and robustness…
Optimal two-qubit states for quantum teleportation vis-à-vis state properties
Arkaprabha Ghosal, Debarshi Das, Saptarshi Roy +1
Quantum teleportation with a two-qubit state can be suitably characterized in terms of maximal fidelity and fidelity deviation, where the former is the maximal value of the average…
Response of macroscopic and microscopic dynamical quantifiers to the quantum critical region
Stav Haldar, Saptarshi Roy, Titas Chanda +1
At finite temperatures, the quantum critical region (QCR) emerges as a consequence of the interplay between thermal and quantum fluctuations. We seek for suitable physical quantiti…
Fidelity deviation in quantum teleportation with a two-qubit state
Arkaprabha Ghosal, Debarshi Das, Saptarshi Roy +1
Quantum teleportation with an arbitrary two-qubit state can be appropriately characterized in terms of maximal fidelity and fidelity deviation. The former quantifies optimality of…
Recycling the resource: Sequential usage of shared state in quantum teleportation with weak measurements
Saptarshi Roy, Anindita Bera, Shiladitya Mal +2
Complete measurements, while providing maximal information gain, results in destruction of the shared entanglement. In the standard teleportation scheme, the sender's measurement o…
Multipartite entanglement at dynamical quantum phase transitions with non-uniformly spaced criticalities
Stav Haldar, Saptarshi Roy, Titas Chanda +2
We report dynamical quantum phase transition portrait in the alternating field transverse XY spin chain with Dzyaloshinskii-Moriya interaction by investigating singularities in the…