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arXiv · 2111.13548

A Sub-Picosecond Digitally-Controlled Phase Delay

Diba Dehmeshki·Erich Frahm·Roger Rusack·Rohith Saradhy·Yahya Tousi
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Abstract

The use of precision timing measurements will be a major tool at the HL-LHC, where it will be used to suppress pile-up and to search for long-lived particles. To control a reference clock with sub-picosecond accuracy, we have fabricated in the TSMC 65 nm process a digitally controlled phase shifter. It is composed of a chain of 66 cells, each with a digitally controlled planar wave guide with either a short or long delay. With this a reference clock's phase can be controlled to a precision of 200 fs with dynamic range of 12 ps.

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Diba Dehmeshki, Erich Frahm, Roger Rusack, Rohith Saradhy, Yahya Tousi. 2021-11-26. A Sub-Picosecond Digitally-Controlled Phase Delay. https://doi.org/10.1088/1748-0221%2F17%2F03%2Fc03014

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