Massachusetts Institute of Technology

International Business Machines Corporation

Wayne Woods

William D Oliver

Andrew J Kerman

Donna-Ruth Webb Yost

Danna Rosenberg

Siva Yegnanarayanan

Mollie Schwartz

Jonilyn L Yoder

Justin Mallek

Cyrus Hirjibehedin

Thomas Hazard

Guoan Wang

Qubit circuits having components formed deep in a substrate are described. The qubit circuits can be manufactured using existing integrated-circuit technologies. By forming components such as superconducting current loops, inductive, and/or capacitive components deep in the substrate, the footprint of the qubit circuit integrated within the substrate can be reduced. Additionally, coupling efficiency to and from the qubit can be improved and losses in the qubit circuit may be reduced.

Qubit circuits with deep, in-substrate components

The performance of an electro-optic modulator depends in part on the capacitance, the inductance, the electric field distribution, and the signal insertion loss of a microwave transmission line that modulates the refractive index of a waveguide via the electro-optic effect. Conventional electro-optic modulators are typically unable to improve one of these properties without negatively affecting other properties, resulting in lower performance. These shortcomings may be overcome, in part, by the inclusion of capacitive structures to decouple these properties. The capacitive structure may include a fang and/or a hook to tune the capacitance and the electric field distribution without appreciably changing the inductance or the signal insertion losses. The inductance and the signal insertion losses may be tuned by changing the sizes and shapes of a signal conductor, a ground conductor, and a slot formed between the signal and ground conductors without appreciably changing the capacitance or the electric field distribution.

Optical modulator RF electrodes

Growing community of inventors

Burlington, MA, United States of America

Wayne Woods