English
Related papers

Related papers: Experimental demonstration of selective quantum pr…

200 papers

Quantum computing using two-dimensional NMR has recently been described using scalar coupling evolution technique [J. Chem. Phys.,109,10603 (1998)]. In the present paper, we describe two-dimensional NMR quantum computing with the help of…

Quantum Physics · Physics 2007-05-23 T. S. Mahesh , Kavita Dorai , Arvind , Anil Kumar

Programmable photonic quantum processors face a critical challenge: despite significant advances in quantum state preparation and manipulation, measurements remain limited to projective techniques. Here, we demonstrate a programmable…

Many applications of quantum simulation require to prepare and then characterize quantum states by performing an efficient partial tomography to estimate observables corresponding to $k$-body reduced density matrices ($k$-RDMs). For…

Quantum Physics · Physics 2020-09-24 Xavier Bonet-Monroig , Ryan Babbush , Thomas E. O'Brien

Experimental realization of quantum information processing in the field of nuclear magnetic resonance (NMR) has been well established. Implementation of conditional phase shift gate has been a significant step, which has lead to realization…

Quantum Physics · Physics 2009-11-10 Ranabir Das , T. S. Mahesh , Anil Kumar

Quantifying and verifying the control level in preparing a quantum state are central challenges in building quantum devices. The quantum state is characterized from experimental measurements, using a procedure known as tomography, which…

Quantum Physics · Physics 2021-12-28 Quoc Hoan Tran , Kohei Nakajima

We employ the compressed sensing (CS) algorithm and a heavily reduced data set to experimentally perform true quantum process tomography (QPT) on an NMR quantum processor. We obtain the estimate of the process matrix $\chi$ corresponding to…

Quantum Physics · Physics 2024-11-05 Akshay Gaikwad , Arvind , Kavita Dorai

Quantum computers have a potential for solving quantum chemistry problems with higher accuracy than classical computers. Quantum computing quantum Monte Carlo (QC-QMC) is a QMC with a trial state prepared in quantum circuit, which is…

Quantum Physics · Physics 2024-06-07 Shu Kanno , Hajime Nakamura , Takao Kobayashi , Shigeki Gocho , Miho Hatanaka , Naoki Yamamoto , Qi Gao

We have investigated the realizability of the controlled-NOT (CNOT) gate and characterized the gate operation by quantum process tomography for a chain of qubits, realized by electrons confined in self-assembled quantum dots embedded in the…

Quantum Physics · Physics 2015-06-04 Makoto Unoki , Hiromichi Nakazato , Kazuya Yuasa , Kanji Yoh

We use a constrained convex optimization (CCO) method to experimentally characterize arbitrary quantum states and unknown quantum processes on a two-qubit NMR quantum information processor. Standard protocols for quantum state and quantum…

Quantum Physics · Physics 2025-10-31 Akshay Gaikwad , Arvind , Kavita Dorai

We propose and analyze the design of a programmable photonic integrated circuit for high-fidelity quantum computation and simulation. We demonstrate that the reconfigurability of our design allows us to overcome two major impediments to…

Quantum Physics · Physics 2015-09-30 Jacob Mower , Nicholas C. Harris , Gregory R. Steinbrecher , Yoav Lahini , Dirk Englund

In building a quantum information processor (QIP), the challenge is to coherently control a large quantum system well enough to perform an arbitrary quantum algorithm and to be able to correct errors induced by decoherence. Nuclear magnetic…

Quantum Physics · Physics 2009-11-13 C. A. Ryan , C. Negrevergne , M. Laforest , E. Knill , R. Laflamme

The reliable characterization of quantum states is a fundamental task in quantum information science. For this purpose, quantum state tomography provides a standard framework for reconstructing quantum states from measurement data, yet it…

Quantum Physics · Physics 2026-04-14 Yixuan Hu , Mengru Ma , Jiangwei Shang

In the light of the progress in quantum technologies, the task of verifying the correct functioning of processes and obtaining accurate tomographic information about quantum states becomes increasingly important. Compressed sensing, a…

Quantum Physics · Physics 2017-05-15 A. Steffens , C. Riofrio , W. McCutcheon , I. Roth , B. A. Bell , A. McMillan , M. S. Tame , J. G. Rarity , J. Eisert

Quantum logic gates must perform properly when operating on their standard input basis states, as well as when operating on complex superpositions of these states. Experiments using superconducting qubits have validated the truth table for…

High performance quantum information processing requires efficient control of undesired decohering effects, which are present in realistic quantum dynamics. To deal with this issue, a powerful strategy is to employ transitionless quantum…

The characterization of a unitary gate is experimentally accomplished via Quantum Process Tomography, which combines the outcomes of different projective measurements to reconstruct the underlying operator. The process matrix is typically…

Quantum Physics · Physics 2025-09-17 Tareq Jaouni , Francesco Di Colandrea , Lorenzo Amato , Filippo Cardano , Ebrahim Karimi

The characterization of a quantum device is a crucial step in the development of quantum experiments. This is accomplished via Quantum Process Tomography, which combines the outcomes of different projective measurements to deliver a…

Quantum Physics · Physics 2025-06-26 Francesco Di Colandrea , Nazanin Dehghan , Alessio D'Errico , Ebrahim Karimi

In Ref. [Phys. Rev. A 100, 062317 (2019)], the authors reported an algorithm to implement, in a circuit-based quantum computer, a general quantum measurement (GQM) of a two-level quantum system, a qubit. Even though their algorithm seems…

Quantum Physics · Physics 2023-02-10 Douglas F. Pinto , Marcelo S. Zanetti , Marcos L. W. Basso , Jonas Maziero

Most quantum processors requires pulse sequences for controlling quantum states. Here, we present an alternative algorithm for computing an optimal pulse sequence in order to perform a specific task, being an implementation of a quantum…

Quantum Physics · Physics 2020-05-27 John P. S. Peterson , Roberto S. Sarthour , Raymond Laflamme

Recently, machine learning had a remarkable impact, from scientific to everyday-life applications. However, complex tasks often imply unfeasible energy and computational power consumption. Quantum computation might lower such requirements,…