TY - GEN
T1 - High-power laser diodes with high polarization purity
AU - Rosenkrantz, Etai
AU - Yanson, Dan
AU - Peleg, Ophir
AU - Blonder, Moshe
AU - Rappaport, Noam
AU - Klumel, Genady
N1 - Publisher Copyright:
© 2017 SPIE.
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Fiber-coupled laser diode modules employ power scaling of single emitters for fiber laser pumping. To this end, techniques such as geometrical, spectral and polarization beam combining (PBC) are used. For PBC, linear polarization with high degree of purity is important, as any non-perfectly polarized light leads to losses and heating. Furthermore, PBC is typically performed in a collimated portion of the beams, which also cancels the angular dependence of the PBC element, e.g., beam-splitter. However, we discovered that single emitters have variable degrees of polarization, which depends both on the operating current and far-field divergence. We present data to show angle-resolved polarization measurements that correlate with the ignition of high-order modes in the slow-axis emission of the emitter. We demonstrate that the ultimate laser brightness includes not only the standard parameters such as power, emitting area and beam divergence, but also the degree of polarization (DoP), which is a strong function of the latter. Improved slow-axis divergence, therefore, contributes not only to high brightness but also high beam combining efficiency through polarization.
AB - Fiber-coupled laser diode modules employ power scaling of single emitters for fiber laser pumping. To this end, techniques such as geometrical, spectral and polarization beam combining (PBC) are used. For PBC, linear polarization with high degree of purity is important, as any non-perfectly polarized light leads to losses and heating. Furthermore, PBC is typically performed in a collimated portion of the beams, which also cancels the angular dependence of the PBC element, e.g., beam-splitter. However, we discovered that single emitters have variable degrees of polarization, which depends both on the operating current and far-field divergence. We present data to show angle-resolved polarization measurements that correlate with the ignition of high-order modes in the slow-axis emission of the emitter. We demonstrate that the ultimate laser brightness includes not only the standard parameters such as power, emitting area and beam divergence, but also the degree of polarization (DoP), which is a strong function of the latter. Improved slow-axis divergence, therefore, contributes not only to high brightness but also high beam combining efficiency through polarization.
KW - Degree of polarization
KW - brightness
KW - fiber coupled emitter
KW - fiber coupling
KW - high-power laser
KW - laser diode
KW - multi-emitter module
KW - polarization beam combining
KW - slow axis divergence
UR - http://www.scopus.com/inward/record.url?scp=85019411200&partnerID=8YFLogxK
U2 - 10.1117/12.2251783
DO - 10.1117/12.2251783
M3 - Conference contribution
AN - SCOPUS:85019411200
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - High-Power Diode Laser Technology XV 2017
A2 - Zediker, Mark S.
PB - SPIE
T2 - High-Power Diode Laser Technology XV 2017
Y2 - 30 January 2017 through 31 January 2017
ER -