English
Related papers

Related papers: Tomography of a spin qubit in a double quantum dot

200 papers

The quantum steering ellipsoid inscribed inside the Bloch sphere offers an elegant geometric visualization of two-qubit states shared between Alice and Bob. The set of Bloch vectors of Bob's qubit, steered by Alice via all possible local…

Quantum Physics · Physics 2023-04-28 K. Anjali , I. Reena , Sudha , B. G. Divyamani , H. S. Karthik , K. S. Mallesh , A. R. Usha Devi

The two-qubit pure state is explicitly parameterized by three unit 2-spheres and a phase factor. For separable states, two of the three unit spheres are the Bloch spheres of each qubit. The third sphere parameterizes the degree and phase of…

Quantum Physics · Physics 2019-07-23 Chu-Ryang Wie

We propose and analyze quantum state estimation (tomography) using continuous quantum measurements with resource limitations, allowing the global state of many qubits to be constructed from only measuring a few. We give a proof-of-principle…

Quantum Physics · Physics 2020-04-13 Areeya Chantasri , Shengshi Pang , Teerawat Chalermpusitarak , Andrew N. Jordan

The spin states of electrons and holes confined in InAs quantum dot molecules have recently come to fore as a promising system for the storage or manipulation of quantum information. We describe here a feasible scheme for complete quantum…

Mesoscale and Nanoscale Physics · Physics 2015-01-09 Guy Z. Cohen

We report initialization, complete electrical control, and single-shot readout of an exchange-only spin qubit. Full control via the exchange interaction is fast, yielding a demonstrated 75 qubit rotations in under 2 ns. Measurement and…

Mesoscale and Nanoscale Physics · Physics 2013-09-09 J. Medford , J. Beil , J. M. Taylor , S. D. Bartlett , A. C. Doherty , E. I. Rashba , D. P. DiVincenzo , H. Lu , A. C. Gossard , C. M. Marcus

We propose a technique for measuring the state of a single donor electron spin using a field-effect transistor induced two-dimensional electron gas and electrically detected magnetic resonance techniques. The scheme is facilitated by…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Mohan Sarovar , Kevin C. Young , Thomas Schenkel , K. Birgitta Whaley

We introduce and experimentally demonstrate a technique for performing quantum state tomography on multiple-qubit states despite incomplete knowledge about the unitary operations used to change the measurement basis. Given unitary…

Quantum tomography makes it possible to obtain comprehensive information about certain logical elements of a quantum computer. In this regard, it is a promising tool for debugging quantum computers. The practical application of tomography,…

Quantum Physics · Physics 2020-12-23 B. I. Bantysh , Yu. I. Bogdanov

In the usual tomography of multipartite entangled quantum states one assumes that the measurement devices used in the laboratory are under perfect control of the experimenter. In this paper, using the so-called SWAP concept introduced…

Quantum Physics · Physics 2014-11-05 Karoly F. Pal , Tamas Vertesi , Miguel Navascues

We consider spin-orbit coupled Bose-Einstein condensates with cubic-quintic nonlinear interaction within the framework of second quantization formulation and find eigen states using numerical simulation and mean-field approximation. We show…

Quantum Gases · Physics 2026-03-30 Prithwish Ghosh , Kajal Krishna Dey , Golam Ali Sekh

An electron inside liquid helium forms a bubble of 17 \AA in radius. In an external magnetic field, the two-level system of a spin 1/2 electron is ideal for the implementation of a qubit for quantum computing. The electron spin is well…

Other Condensed Matter · Physics 2007-05-23 Weijun Yao

We establish the relation of the spin tomogram to the Wigner function on a discrete phase space of qubits. We use the quantizers and dequantizers of the spin tomographic star-product scheme for qubits to derive the expression for the kernel…

We review the progress and main challenges in implementing large-scale quantum computing by optical control of electron spins in quantum dots (QDs). Relevant systems include self-assembled QDs of III-V or II-VI compound semiconductors (such…

Quantum Physics · Physics 2010-09-13 Ren-Bao Liu , Wang Yao , L. J. Sham

Quantum state tomography is a fundamental tool in quantum information processing. It allows us to estimate the state of a quantum system by measuring different observables on many identically prepared copies of the system. This is, in…

Quantum Physics · Physics 2011-11-28 Carlos A. Riofrío

We present an approach for entangling electron spin qubits localized on spatially separated impurity atoms or quantum dots via a multi-electron, two-level quantum dot. The effective exchange interaction mediated by the dot can be understood…

Mesoscale and Nanoscale Physics · Physics 2015-06-10 V. Srinivasa , H. Xu , J. M. Taylor

State tomography on qubit pairs is routinely carried out by measuring the two qubits separately, while one expects a higher efficiency from tomography with highly symmetric joint measurements of both qubits. Our numerical study of simulated…

Quantum Physics · Physics 2015-05-13 Yong Siah Teo , Huangjun Zhu , Berthold-Georg Englert

Tomography is an indispensable part of quantum computation as it enables diagnosis of a quantum process through state reconstruction. Existing tomographic protocols are based on determining expectation values of various Pauli operators…

Quantum Physics · Physics 2021-03-26 Tanay Roy , Ziqian Li , Eliot Kapit , David I. Schuster

Quantum state tomography is a central technique for the characterization and verification of quantum systems. Standard tomography is widely used for low-dimensional systems, but for larger systems, it becomes impractical due to the…

We propose a scheme for implementing quantum gates and entanglement between spin qubits in the outer dots of a triple-dot system with an empty central dot. The voltage applied to the central dot can be tuned to realize the gate. Our scheme…

Quantum Physics · Physics 2015-03-19 Jose Garcia Coello , Sougato Bose

We propose a tomographic reconstruction scheme for spin states. The experimental setup, which is a modification of the Stern-Gerlach scheme, can be easily performed with currently available technology. The method is generalized to…

Quantum Physics · Physics 2009-11-07 G. M. D'Ariano , L. Maccone , M. Paini
‹ Prev 1 4 5 6 7 8 10 Next ›