22 citations · 135 across the 31 of their papers we have counts for
31 papers
Network steering with arbitrarily low detection efficiency of any entangled measurement
Shubhayan Sarkar
Quantum nonlocality and its asymmetric counterpart, quantum steering, are among the most intriguing manifestations of quantum mechanics. From a theoretical perspective, they are no…
Polytopic Quantum Resource Theories: Geometry and Structures
Moein Naseri, Chirag Srivastava, Chandan Datta +2
Quantum resource theories provide a unifying framework to quantify, compare, and manipulate quantum resources under well-defined operational constraints. Here, we consider any reso…
Predictive supremacy of informationally-restricted quantum perceptron
Shubhayan Sarkar
In the current world, the use of artificial intelligence is penetrating every aspect of human life. The basic element of any artificial intelligence is a digital neuron, called a p…
Entanglement is not sufficient for most practical entanglement-based QKD protocols
Shubhayan Sarkar, Tushita Prasad, Karol Horodecki
Quantum key distribution (QKD) is the most explored application of quantum information theory. A central problem in entanglement-based QKD (EB-QKD), is whether every entangled stat…
Classifying the simplest Bell inequalities beyond qubits and their applications towards self-testing
Palash Pandya, Shubhayan Sarkar, Remigiusz Augusiak
Bell inequalities reveal the fundamentally nonlocal character of quantum mechanics. In this regard, one of the interesting problems is to explore all possible Bell inequalities tha…
Any gate of a quantum computer can be certified device-independently
Shubhayan Sarkar
Device-independent (DI) certification allows the verification of quantum systems based solely on observed statistics, without assumptions about their internal structure. While self…
Topologically noise robust network steering without inputs
Dhruv Baheti, Shubhayan Sarkar
Quantum networks with independent sources allow observing quantum nonlocality or steering with just a single measurement per node of the network, or without any inputs. Inspired by…
Gap between quantum theory based on real and complex numbers is arbitrarily large
Shubhayan Sarkar, David Trillo, Marc Olivier Renou +1
Quantum Information Theory, the standard formalism used to represent information contained in quantum systems, is based on complex Hilbert spaces (CQT). It was recently shown that…
Detecting entanglement in any measurement using quantum networks
Shubhayan Sarkar
Entanglement is a key resource to demonstrate quantum advantage over classical strategies. Entanglement in quantum states is one of the most well-explored areas in quantum physics.…
Using quantum nonlocality for device-independent confirmation of relativistic effects
Shubhayan Sarkar
Synchronizing clocks to measure time is a fundamental process underpinning every practical communication task from GPS to parallel computation. However, as the current protocols ar…
Detecting quantum resources in a semi-device independent framework
Shubhayan Sarkar, Chandan Datta
We investigate whether one can detect the presence of a quantum resource in some operational task or equivalently whether every quantum resource provides an advantage over its free…
Witnessing network steerability of every bipartite entangled state without inputs
Shubhayan Sarkar
Quantum steering is an asymmetric form of quantum nonlocality where one can detect whether a measurement on one system can steer or change another distant system. It is well-known…
One-sided DI-QKD secure against coherent attacks over long distances
Michele Masini, Shubhayan Sarkar
Quantum Key Distribution (QKD) is a technique enabling provable secure communication but faces challenges in device characterization, posing potential security risks. Device-Indepe…
Model-independent inference of quantum interaction from statistics
Shubhayan Sarkar
Any physical theory aims to establish the relationship between physical systems in terms of the interaction between these systems. However, any known approach in the literature to…
Almost device-independent certification of GME states with minimal measurements
Shubhayan Sarkar, Alexandre C. Orthey, Gautam Sharma +2
Device-independent certification of quantum states enables the characterization of states within a device under minimal physical assumptions. A major problem in this regard is to c…
A universal scheme to self-test any quantum state or measurement
Shubhayan Sarkar, Alexandre C. Orthey, Remigiusz Augusiak
The emergence of quantum devices has raised a significant issue: how to certify the quantum properties of a device without placing trust in it. To characterise quantum states and m…
Shared randomness allows violation of macroscopic realism using a single measurement
Shubhayan Sarkar
Macro-realistic description of systems is based majorly on two basic intuitions about the classical world, namely, macrorealism per se, that is, the system is always in a distinct…
Operationally independent events can influence each other in quantum theory
Shubhayan Sarkar
In any known description of nature, two physical systems are considered independent of each other if any action on one of the systems does not change the other system. From our cla…
Distrustful quantum steering
Shubhayan Sarkar
Quantum steering is an asymmetric form of quantum nonlocality where one can trust the measurements of one of the parties. In this work, inspired by practical considerations we inve…
Certification of randomness without seed randomness
Shubhayan Sarkar
The security of any cryptographic scheme relies on access to random number generators. Device-independently certified random number generators provide maximum security as one can d…
Network quantum steering enables randomness certification without seed randomness
Shubhayan Sarkar
Quantum networks with multiple sources allow the observation of quantum nonlocality without inputs. Consequently, the incompatibility of measurements is not a necessity for observi…
Certification of unbounded randomness with arbitrary noise
Shubhayan Sarkar
Random number generators play an essential role in cryptography and key distribution. It is thus important to verify whether the random numbers generated from these devices are gen…
Certification of entangled quantum states and quantum measurements in Hilbert spaces of arbitrary dimension
Shubhayan Sarkar
The emergence of quantum theory at the beginning of 20 century has changed our view of the microscopic world and has led to applications such as quantum teleportation, quantum…
Self-testing composite measurements and bound entangled state in a single quantum network
Shubhayan Sarkar, Chandan Datta, Saronath Halder +1
Within the quantum networks scenario we introduce a single scheme allowing to certify three different types of composite projective measurements acting on a three-qubit Hilbert spa…