Shaddock, DanielBuchler, BenjaminBowen, Warwick PGray, MalcolmLam, Ping Koy2015-12-132015-12-131464-4258http://hdl.handle.net/1885/88981We present results for continuous-wave second-harmonic generation of 532 nm light in an external cavity locked using a spatial mode interference technique. This technique does not require frequency modulation and thus yields a clean second-harmonic spectrum devoid of modulation sidebands. The performance is compared with the same system controlled by Pound-Drever-Hall locking. Both techniques achieved the same maximum output power with comparable stability which is predominantly limited by fluctuations in the pump power and the nonlinear crystal temperature.Keywords: Light modulation; Light polarization; Spectrum analysis; Wave interference; Tilt lockings; Second harmonic generation200010.1088/1464-4258/2/5/3092015-12-12