Qucor Pty Limited

Quocor Pty. Ltd.

Unisearch Limited

Alexander Rudolf Hamilton

Andrew Steven Dzurak

Robert Graham Clark

Lloyd Christopher Leonard Hollenberg

Cameron Wellard

Rolf Brenner

Gerard J Milburn

David J Reilly

Michelle Yvonne Simmons

Toby Hallam

Neil Jonathan Curson

Lars Oberbeck

Mladen Mitic

Andrew Greentree

Frank J Ruess

K E Johnson Goh

Frederick Green

Tilo Marcus Buehler

Nancy Ellen Lumpkin

Rita Paytricia McKinnon

This invention concerns a quantum device, suitable for quantum computing, based on dopant atoms located in a solid semiconductor or insulator substrate. In further aspects the device is scaled up. The invention also concerns methods of reading out from the devices, initializing them, using them to perform logic operations and making them.

Solid state charge qubit device

Ionisation of one of a pair of dopant atoms in a substrate creates a double well potential, and a charge qubit is realised by the location of one or more electrons or holes within this potential. The dopant atoms may comprise phosphorous atoms, located in a silicon substrate. A solid state quantum computer may be formed using a plurality of pairs of dopant atoms, corresponding gate electrodes, and read-out devices comprising single electron transistors.

This invention concerns the fabrication of nanoscale and atomic scale devices. The method involves creating one or more registration markers. Using a SEM or optical microscope to form an image of the registration markers and the tip of a scanning tunnelling microscope (STM). Using the image to position and reposition the STM tip to pattern the device structure. Forming the active region of the device and then encapsulating it such that one or more of the registration markers are still visible to allow correct positioning of surface electrodes. The method can be used to form any number of device structures including quantum wires, single electron transistors, arrays or gate regions. The method can also be used to produce 3D devices by patterning subsequent layers with the STM and encapsulating in between.

Fabricating nanoscale and atomic scale devices

This invention concerns quantum computers in which the qubits are closed systems, in that the particle or particles are confined within the structure. A 'site' can be produced by any method of confining an electron or other quantum particle, such as a dopant atom, a quantum dot, a cooper pair box, or any combination of these. In particular the invention concerns a closed three-site quantum particle system. The state in the third site is weakly coupled by coherent tunneling to the first and second states, so that the third state is able to map out the populations of the first and second states as its energy is scanned with respect to the first and second states. In second and third aspects it concerns a readout method for a closed three-state quantum particle system.

Qubit readout via controlled coherent tunnelling to probe state

A silicon substrate is coated with one or more layers of resist. First and second circuit patterns are exposed in sequence, where the second pattern crosses the first pattern. The patterned resist layers are developed to open holes which extend down to the substrate only where the patterns cross over each other. These holes provide a mask suitable for implanting single phosphorous ions in the substrate, for a solid state quantum computer. Further development of the resist layers provides a mask for the deposition of nanoelectronic circuits, such as single electron transistors, aligned to the phosphorous ions.

Fabrication of nanoelectronic circuits

Growing community of inventors

Forestville, Australia

Alexander Rudolf Hamilton