Phys.org September 10, 2021 Researchers in Japan have developed a device consisting of a triple quantum dot on a silicon/silicon–germanium heterostructure and controlled through aluminum gates. Each quantum dot can host one electron, whose spin-up and spin-down states encode a qubit. An on-chip magnet generates a magnetic-field gradient that separates the resonance frequencies of the three qubits, so that they can be individually addressed. They first entangled two of the qubits by implementing a two-qubit gate and then realized three-qubit entanglement by combining the third qubit and the gate. The resulting three-qubit state had a remarkably high state fidelity of […]
Tag Archives: Spin qubits
Physicists break distance record for electron spin-state transmission in spin qubits
Physics World October 10, 2019 A team of researchers in the US (University of Rochester, Purdue University) has demonstrated coherent spin-state transfer along an array of four electrons confined in a quadruple quantum dot in a GaAs/AlGaAs heterostructure. When they applied a voltage pulse to a gate between two quantum dots, the electrons in the dots exchanged their spin states via Heisenberg exchange coupling. By applying a series of voltage pulses to specific gates, the researchers were able to shuttle the spin states of the electrons back and forth. They were able to transmit the spins of entangled electrons using […]