Limits...
10-W pulsed operation of substrate emitting photonic-crystal quantum cascade laser with very small divergence.

Yao DY, Zhang JC, Cathabard O, Zhai SQ, Liu YH, Jia ZW, Liu FQ, Wang ZG - Nanoscale Res Lett (2015)

Bottom Line: High-power broad area substrate emitting photonic-crystal distributed feedback (DFB) quantum cascade lasers (QCLs) emitting around 4.73 μm is reported.Two-dimensional centered rectangular photonic-crystal (CRPC) grating is introduced to enhance optical coherence in large area device.Main lobe far-field radiation pattern with a very small divergence angle of about 0.65° × 0.31° is obtained.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083 China.

ABSTRACT
High-power broad area substrate emitting photonic-crystal distributed feedback (DFB) quantum cascade lasers (QCLs) emitting around 4.73 μm is reported. Two-dimensional centered rectangular photonic-crystal (CRPC) grating is introduced to enhance optical coherence in large area device. Main lobe far-field radiation pattern with a very small divergence angle of about 0.65° × 0.31° is obtained. A record peak output power for vertical emitting QCLs exceeding 10 W is obtained with high reflectivity (HR) coating. Robust single longitudinal mode emission with a side mode suppression ratio (SMSR) of 30 dB is continuously tunable by the heat sink temperature up to 65°C.

No MeSH data available.


Related in: MedlinePlus

Power versus current (L-I) characterization of a 4-mm-long CRPC substrate emitting QCL. With a ridge width of 390 μm at different heat sink temperatures between 10°C and 50°C. The inset shows the semilog plot of single-mode emission spectra at an injection current of 1.1Ith under pulsed mode operation, and a SMSR of 30 dB is maintained for the entire temperature range of 15°C to 65°C. Device edge facets were high-reflective coated, and substrate facets were anti-reflective coated.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4402689&req=5

Fig4: Power versus current (L-I) characterization of a 4-mm-long CRPC substrate emitting QCL. With a ridge width of 390 μm at different heat sink temperatures between 10°C and 50°C. The inset shows the semilog plot of single-mode emission spectra at an injection current of 1.1Ith under pulsed mode operation, and a SMSR of 30 dB is maintained for the entire temperature range of 15°C to 65°C. Device edge facets were high-reflective coated, and substrate facets were anti-reflective coated.

Mentions: Our devices realized high-power operation above room temperature in pulsed mode with a pulse width of 400 ns and repetition frequency of 5 kHz. Figure 4 shows the power versus current (L-I) characterization of a 4-mm-long CRPC substrate emitting QCL with ridge width of 390 μm at different heat sink temperatures. At 10°C, the laser emits up to maximum peak power of 10.3 W with slope efficiencies around 0.38 W/A and threshold current density around 1.86 kA/cm2. The maximum wall plug efficiency (WPE) of 1.1% was obtained at a current of 60 A. When the temperature rises up to 50°C, the corresponding value drops to 7.7 W, 0.29 W/A and increases to 2.15 kA/cm2. The inset of Figure 4 shows the semilog plot of single-mode emission spectra at an injection current of 1.1Ith between 15°C and 65°C with a step of 5°C. Single longitudinal mode emission with a side mode suppression ratio (SMSR) of about 30 dB at the entire temperature range is obtained. The peak emission spectrum is observed to shift from 2,112.4 cm−1 at 15°C to 2,104.6 cm−1 at 65°C, corresponding to a temperature tuning coefficient ∇v/∇T = −0.155 cm−1 C−1.Figure 4


10-W pulsed operation of substrate emitting photonic-crystal quantum cascade laser with very small divergence.

Yao DY, Zhang JC, Cathabard O, Zhai SQ, Liu YH, Jia ZW, Liu FQ, Wang ZG - Nanoscale Res Lett (2015)

Power versus current (L-I) characterization of a 4-mm-long CRPC substrate emitting QCL. With a ridge width of 390 μm at different heat sink temperatures between 10°C and 50°C. The inset shows the semilog plot of single-mode emission spectra at an injection current of 1.1Ith under pulsed mode operation, and a SMSR of 30 dB is maintained for the entire temperature range of 15°C to 65°C. Device edge facets were high-reflective coated, and substrate facets were anti-reflective coated.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4402689&req=5

Fig4: Power versus current (L-I) characterization of a 4-mm-long CRPC substrate emitting QCL. With a ridge width of 390 μm at different heat sink temperatures between 10°C and 50°C. The inset shows the semilog plot of single-mode emission spectra at an injection current of 1.1Ith under pulsed mode operation, and a SMSR of 30 dB is maintained for the entire temperature range of 15°C to 65°C. Device edge facets were high-reflective coated, and substrate facets were anti-reflective coated.
Mentions: Our devices realized high-power operation above room temperature in pulsed mode with a pulse width of 400 ns and repetition frequency of 5 kHz. Figure 4 shows the power versus current (L-I) characterization of a 4-mm-long CRPC substrate emitting QCL with ridge width of 390 μm at different heat sink temperatures. At 10°C, the laser emits up to maximum peak power of 10.3 W with slope efficiencies around 0.38 W/A and threshold current density around 1.86 kA/cm2. The maximum wall plug efficiency (WPE) of 1.1% was obtained at a current of 60 A. When the temperature rises up to 50°C, the corresponding value drops to 7.7 W, 0.29 W/A and increases to 2.15 kA/cm2. The inset of Figure 4 shows the semilog plot of single-mode emission spectra at an injection current of 1.1Ith between 15°C and 65°C with a step of 5°C. Single longitudinal mode emission with a side mode suppression ratio (SMSR) of about 30 dB at the entire temperature range is obtained. The peak emission spectrum is observed to shift from 2,112.4 cm−1 at 15°C to 2,104.6 cm−1 at 65°C, corresponding to a temperature tuning coefficient ∇v/∇T = −0.155 cm−1 C−1.Figure 4

Bottom Line: High-power broad area substrate emitting photonic-crystal distributed feedback (DFB) quantum cascade lasers (QCLs) emitting around 4.73 μm is reported.Two-dimensional centered rectangular photonic-crystal (CRPC) grating is introduced to enhance optical coherence in large area device.Main lobe far-field radiation pattern with a very small divergence angle of about 0.65° × 0.31° is obtained.

View Article: PubMed Central - PubMed

Affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing, 100083 China.

ABSTRACT
High-power broad area substrate emitting photonic-crystal distributed feedback (DFB) quantum cascade lasers (QCLs) emitting around 4.73 μm is reported. Two-dimensional centered rectangular photonic-crystal (CRPC) grating is introduced to enhance optical coherence in large area device. Main lobe far-field radiation pattern with a very small divergence angle of about 0.65° × 0.31° is obtained. A record peak output power for vertical emitting QCLs exceeding 10 W is obtained with high reflectivity (HR) coating. Robust single longitudinal mode emission with a side mode suppression ratio (SMSR) of 30 dB is continuously tunable by the heat sink temperature up to 65°C.

No MeSH data available.


Related in: MedlinePlus