Södergren Lasse, Olausson Patrik, Lind Erik
Department of Electrical and Information Technology, Lund University, Box 118, SE-221 00 Lund, Sweden.
NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden.
Nano Lett. 2022 May 25;22(10):3884-3888. doi: 10.1021/acs.nanolett.1c04971. Epub 2022 May 12.
In current quantum computers, most qubit control electronics are connected to the qubit chip inside the cryostat by cables at room temperature. This poses a challenge when scaling the quantum chip to an increasing number of qubits. We present a lateral nanowire network 1-to-4 demultiplexer design fabricated by selective area grown InGaAs on InP, suitable for on chip routing of DC current for qubit biasing. We have characterized the device at cryogenic temperatures, and at 40 mK the device exhibits a minimum inverse subthreshold slope of 2 mV/dec, which is encouraging for low power operation. At low drain bias, the transmission breaks up into several resonance peaks due to a rough conduction band edge; this is qualitatively explained by a simple model based on a 1D real space tight-binding nonequilibrium Green's functions model.
在当前的量子计算机中，大多数量子比特控制电子设备通过室温下的电缆连接到低温恒温器内的量子比特芯片。当将量子芯片扩展到越来越多的量子比特时，这带来了挑战。我们展示了一种通过在InP上选择性区域生长InGaAs制造的横向纳米线网络1到4解复用器设计，适用于用于量子比特偏置的直流电流的片上路由。我们在低温温度下对该器件进行了表征，在40 mK时该器件表现出最小亚阈值斜率为2 mV/dec，这对于低功耗运行是令人鼓舞的。在低漏极偏置下，由于粗糙的导带边缘，传输分裂为几个共振峰；这通过基于一维实空间紧束缚非平衡格林函数模型的简单模型进行了定性解释。
