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Search Publications by: William Groman (Assoc)

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Displaying 1 - 4 of 4

Photonic Millimeter-wave Generation Beyond the Cavity Thermal Limit

February 11, 2025
Author(s)
William Groman, Igor Kudelin, Takuma Nakamura, Yifan Liu, Charles McLemore, Franklyn Quinlan, Scott Diddams, Dahyeon Lee, Megan Kelleher, Joel Guo, Warren Jin, John Bowers
With the next generation of telecommunications and radar/navigation upon us, moving from the microwave to the higher bandwidth, millimeter-wave domain has become ever relevant. Simultaneously, the burgeoning field of photonic integrated chips has yielded a

Tunable X-band opto-electronic synthesizer with ultralow phase noise

March 29, 2024
Author(s)
Igor Kudelin, Pedram Shirmohammadi, William Groman, Samin Hanifi, Megan Kelleher, Dahyeon Lee, Takuma Nakamura, Charles McLemore, Steven Bowers, Franklyn Quinlan, Scott Diddams
Microwave signals with low phase noise in the X-band (8-12 GHz) are essential for widespread technologies and important scientific developments. Photonic techniques, such as optical frequency division (OFD), leverage the high spectral purity of low-noise

Photonic chip-based low noise microwave oscillator

March 6, 2024
Author(s)
Igor Kudelin, William Groman, Scott Diddams, Dahyeon Lee, Megan Kelleher, Takuma Nakamura, Charles McLemore, Franklyn Quinlan, Qing-Xin Ji, Joel Guo, Andrey Matsko, John Bowers, Kerry Vahala, Warren Jin, Lue Wu, Yifan Liu, Wei Zhang, Steven Bowers, Joe Campbell, Pedram Shirmohammadi, Samin Hanifi, Haotian Cheng, Naijun Jin, Sam Halliday, Zhaowei Dai, Chao Xiang, Vladimir Iltchenko, Owen Miller, Peter Rakich
Numerous modern technologies are reliant on the low-phase noise and timing stability performance of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low noise microwave signals are generated by the down

Low-noise microwave generation with an air-gap optical reference cavity

January 30, 2024
Author(s)
Yifan Liu, Dahyeon Lee, Takuma Nakamura, Naijun Jin, Haotian Cheng, Megan Kelleher, Charles McLemore, Igor Kudelin, William Groman, Scott Diddams, Peter Rakich, Franklyn Quinlan
We demonstrate a high finesse, microfabricated mirror-based, air-gap cavity with volume less than 1 ml, constructed in an array, that can support low-noise microwave generation through optical frequency division. We use the air-gap cavity in conjunction