Quadrature amplitude modulation for electronic sideband Pound-Drever-Hall locking
| Autor: | Tu, J., Restelli, A., Tsui, T. -C., Weber, K., Spielman, I. B., Rolston, S. L., Porto, J. V., Subhankar, S. |
|---|---|
| Rok vydání: | 2024 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| Popis: | The Pound-Drever-Hall (PDH) technique is routinely used to stabilize the frequency of a laser to a reference cavity. The electronic sideband (ESB) locking scheme, a PDH variant, helps bridge the frequency difference between the quantized frequencies enforced by the cavity and the laser frequency of interest. Here we use quadrature amplitude modulation (QAM), a technique used in digital signal communication, to engineer the high-quality phase-modulated radio-frequency (rf) signal required for ESB locking scheme. We develop a theoretical framework to analyze the effects of in-phase/quadrature-phase (I/Q) impairments on the ESB error signal for ultra-narrow linewidth lasers. We design and implement two baseband-sampling software-defined radio variants for implementing QAM that compensate for these I/Q impairments. Using these variants, we engineer high-quality phase-modulated radio-frequency (rf) signals with a large phase modulation index of 1.01 radians, a maximum modulation frequency of 3 MHz, a tunable carrier wave frequency range of 450 MHz to 4 GHz, and I/Q errors of less than 2.25 % over the entire carrier wave frequency range. Comment: 11 pages, 7 figures |
| Databáze: | arXiv |
| Externí odkaz: |
|