# Quantum logic gates from time-dependent global magnetic field in a system with constant exchange

## Abstract

We propose a method that implements a universal set of one- and two-quantum-bit gates for quantum computation in a system of coupled electron pairs with constant non-diagonal exchange interaction. In our proposal, suppression of the exchange interaction is performed by the continual repetition of single-spin rotations. A small g-factor difference between the electrons allows for addressing qubits and avoiding strong magnetic field pulses. Numerical experiments were performed to show that, to implement the one- and two-qubit operations, it is sufficient to change the strength of the magnetic field by a few Gauss. This introduces one and then the other electron in a resonance. To determine the evolution of the two-qubit system, we use the algorithms of optimal control theory.

- Authors:

- Rzhanov Institute of Semiconductor Physics SB RAS, 630090 Novosibirsk (Russian Federation)
- (Russian Federation)
- Institute for System Dynamics and Control Theory SB RAS, 664033 Irkutsk (Russian Federation)

- Publication Date:

- OSTI Identifier:
- 22399304

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALGORITHMS; ELECTRON PAIRS; ELECTRONS; EXCHANGE INTERACTIONS; LANDE FACTOR; MAGNETIC FIELDS; OPTIMAL CONTROL; QUANTUM COMPUTERS; QUBITS; ROTATION; SPIN; TIME DEPENDENCE

### Citation Formats

```
Nenashev, A. V., E-mail: nenashev@isp.nsc.ru, Dvurechenskii, A. V., Novosibirsk State University, 630090 Novosibirsk, Zinovieva, A. F., Gornov, A. Yu., and Zarodnyuk, T. S.
```*Quantum logic gates from time-dependent global magnetic field in a system with constant exchange*. United States: N. p., 2015.
Web. doi:10.1063/1.4915347.

```
Nenashev, A. V., E-mail: nenashev@isp.nsc.ru, Dvurechenskii, A. V., Novosibirsk State University, 630090 Novosibirsk, Zinovieva, A. F., Gornov, A. Yu., & Zarodnyuk, T. S.
```*Quantum logic gates from time-dependent global magnetic field in a system with constant exchange*. United States. doi:10.1063/1.4915347.

```
Nenashev, A. V., E-mail: nenashev@isp.nsc.ru, Dvurechenskii, A. V., Novosibirsk State University, 630090 Novosibirsk, Zinovieva, A. F., Gornov, A. Yu., and Zarodnyuk, T. S. Sat .
"Quantum logic gates from time-dependent global magnetic field in a system with constant exchange". United States.
doi:10.1063/1.4915347.
```

```
@article{osti_22399304,
```

title = {Quantum logic gates from time-dependent global magnetic field in a system with constant exchange},

author = {Nenashev, A. V., E-mail: nenashev@isp.nsc.ru and Dvurechenskii, A. V. and Novosibirsk State University, 630090 Novosibirsk and Zinovieva, A. F. and Gornov, A. Yu. and Zarodnyuk, T. S.},

abstractNote = {We propose a method that implements a universal set of one- and two-quantum-bit gates for quantum computation in a system of coupled electron pairs with constant non-diagonal exchange interaction. In our proposal, suppression of the exchange interaction is performed by the continual repetition of single-spin rotations. A small g-factor difference between the electrons allows for addressing qubits and avoiding strong magnetic field pulses. Numerical experiments were performed to show that, to implement the one- and two-qubit operations, it is sufficient to change the strength of the magnetic field by a few Gauss. This introduces one and then the other electron in a resonance. To determine the evolution of the two-qubit system, we use the algorithms of optimal control theory.},

doi = {10.1063/1.4915347},

journal = {Journal of Applied Physics},

number = 11,

volume = 117,

place = {United States},

year = {Sat Mar 21 00:00:00 EDT 2015},

month = {Sat Mar 21 00:00:00 EDT 2015}

}