Experimental Quantum Computation with Molecules

Nanjian Wu

Susanne F. Yelin, K. Kirby, Robin Côté

We show how ultracold polar molecules, suggested as a new platform for quantum computation, can be manipulated to switch ``on'' and ``off'' their strong dipole-dipole interactions. This can be accomplished through selective excitation of states with considerably different dipole moments. We discuss different schemes for quantum gates using real molecules: CO, LiH, and CaF, as examples of polar molecules which are being experimentally studied at ultracold temperatures. These schemes can be realized in several recently proposed architectures.

康 近藤, 幹夫 中原, 和也 畑 +1 more

A Hamiltonian in the rotating frame is derived for NMR quantum computing with homonucleus molecules as its computational resource. It is theoretically shown that control pulses designed for heteronucleus spins can be translated to pulses for homonucleus spins by simply replacing hard pulses by soft pulses with properly chosen pulse width. Several experiments employing cytosine as a homonucleus molecule are conducted and it is proved experimentally that the above Hamiltonian accurately describes the dynamics of the spins.

Neil Gershenfeld, Isaac L. Chuang

Harshdeep Singh, Sonjoy Majumder, Sabyashachi Mishra

Du Jiang-Feng, Shi Ming-Jun, Zhou Xian-Yi +5 more

We present the experimental realization of this gate with a solution of chlorostyrene molecules. Our method does not depend heavily on the two-qubit controlled operation, which used to serve as the basic quantum operation in quantum computing. At present, we use transition operator that can be applied to all qubits in one operation. It appears that no experimental realization has yet been reported up to now regarding the implementation of quantum Toffoli gate using transition pulse on three-qubit nuclear magnetic resonance quantum computers. In addition, our method is experimentally convenient to be extended to more qubits.