Altering the colour of quantum gentle on an built-in chip

Change the colour of single photons utilizing the built-in section modulator. Credit score: Loncar Laboratory/Harvard College SEAS.

Optical photons are best carriers of quantum info. However to work collectively in a quantum laptop or community, they should have the identical coloration – or frequency – and bandwidth. Altering the frequency of a photon requires altering its vitality, which is very troublesome for built-in photonic chips.

Just lately, researchers on the Harvard John A. Paulson College of Engineering and Utilized Sciences (SEAS) have developed an built-in electro-optical modulator that may effectively change the frequency and bandwidth of single photons. The system can be utilized for extra superior quantum computing and quantum networks.

Analysis revealed in Gentle: science and purposes.

Changing a photon from one coloration to a different is normally accomplished by sending the photon right into a crystal, via which a robust laser shines, a course of that tends to be inefficient and noisy. Part modulation, during which the oscillations of a photon wave are accelerated or slowed down to alter the photon’s frequency, presents a extra environment friendly methodology, however the system wanted for such a course of, an electro-optical section modulator, has proved troublesome to combine right into a chip.

One materials could also be best for this software: thin-film lithium niobate.

“In our work, we adopted a novel thin-film lithium niobate modulator design that considerably improved system efficiency,” stated Marko Loncar, Tiancai Lin professor {of electrical} engineering at SEAS and senior writer of the examine. “With this built-in modulator, we’ve got achieved a report excessive single photon terahertz frequency shift.”

The workforce additionally used the identical modulator as a “time lens” – a magnifying glass that bends gentle in time quite than area – to alter the photon’s spectral form from thick to skinny.

“Our system is way more compact and vitality environment friendly than conventional mainstream units,” stated Di Zhu, first writer of the paper. “It may be built-in with a variety of classical and quantum units on a single chip to appreciate extra complicated quantum gentle management.”

Dee is a former SEAS Analysis Fellow and is at present a Analysis Fellow on the Company for Science, Analysis and Expertise (A*STAR) in Singapore.

Subsequent, the workforce plans to make use of the system to manage the frequency and bandwidth of quantum emitters for purposes in quantum networks.

The examine was a collaboration between Harvard, MIT, HyperLight, and A*STAR.

Co-authored with Changchen Chen, Mengjie Yu, Linbo Shao, Yaowen Hu, CJ Xin, Matthew Yeh, Soumya Ghosh, Lingyan He, Christian Reimer, Neil Sinclair, Franco NC Wong and Mian Zhang.

Extra Info:
Di Zhu et al., Spectral management of non-classical gentle pulses utilizing a built-in lithium niobate thin-film modulator, Gentle: science and purposes (2022). DOI: 10.1038/s41377-022-01029-7

Courtesy of Harvard John A. Paulson College of Engineering and Utilized Science.

Quote: Quantum Gentle Coloration Change on an Built-in Chip (December 1, 2022), retrieved December 2, 2022, from

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