High-Efficiency Fiber Combining of Long-Wave Infrared Quantum Cascade Lasers

Meng Zhang; Xin Wang; Suhui Yang; Bao Li; Zhuo Li; Jinying Zhang; Yanze Gao

doi:10.3788/AOS231973

Acta Optica Sinica, Volume. 44, Issue 8, 0814003(2024)

High-Efficiency Fiber Combining of Long-Wave Infrared Quantum Cascade Lasers

Meng Zhang¹, Xin Wang^1,2、*, Suhui Yang^1,2,3, Bao Li⁴, Zhuo Li^1,2, Jinying Zhang^1,2, and Yanze Gao^1,2

Author Affiliations

¹School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China

²Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology, Beijing Institute of Technology, Beijing 100081, China

³Key Laboratory of Information Photonics Technology, Ministry of Industry and Information Technology, Beijing Institute of Technology, Beijing 100081, China

⁴The Eleventh Research Institute of China Electronic Science and Technology Group Corporation, Beijing 100015, China

show less

Abstract Get PDF(in Chinese)

Figures & Tables(22)

Fig. 1. Schematic diagram of fiber-coupled optical system

Download full size

Fig. 2. Simulation results of divergent angles of collimated beams. (a) Divergent angle of point-source QCL collimator; (b) divergent angle of extended-source QCL collimator with (0 mm, 0 mm) field of view; (c) divergent angle of extended-source QCL collimator with ( $-$ 0.004 mm, $-$ 0.005 mm) field of view; (d) divergent angle of extended-source QCL collimator with (0.004 mm, 0.005 mm) field of view

Download full size

Fig. 3. Simulation results of divergent angles of two collimators. (a) Point-source QCL collimator; (b) extended-source QCL collimator

Download full size

Fig. 4. Simulated intensity distributions of collimated beams. (a) QCL collimator with NA of 0.68; (b) QCL collimator with NA of 0.83

Download full size

Fig. 5. Simulation result of single-channel fiber-tcoupling system. (a) Laser spot on input surface of fiber; (b) laser spot at 0.1 mm away from output surface of fiber

Download full size

Fig. 6. Single-mode hollow core fiber combiner. (a) Structure diagram of hollow core fiber; (b) transmission loss of single-mode hollow core fiber; (c) picture of single-mode hollow core fiber; (d) picture of single-mode 4×1 hollow core fiber combiner; (e) picture of output surface of single-mode hollow core 4 in 1 fiber combiner under microscope

Download full size

Fig. 7. Schematic diagram of fiber combining experimental system

Download full size

Fig. 8. Experimental setup of single-mode fiber coupling system

Download full size

Fig. 9. Picture of QCL collimator and fiber coupler. (a) QCL collimator with NA of 0.83; (b) fiber coupler

Download full size

Fig. 10. Experimental results of coupling of single-mode long wave infrared hollow core fiber. (a) Fiber output power; (b) fiber coupling efficiency

Download full size

Fig. 11. QCL collimating spot and fiber coupling output spot. (a) QCL collimating spot; (b) fiber coupling output spot

Download full size

Fig. 12. Experimental setup of 4×1 fiber combining system

Download full size

Fig. 13. Experimental results of QCL 4×1 fiber combining. (a) Fiber coupling output power; (b) total fiber output efficiency and total system coupling efficiency

Download full size

Fig. 14. Combined QCL beam spots at different positions along beam propagation direction. (a) $-$ 50 mm; (b) 0 mm; (c) 100 mm; (d) 150 mm

Download full size

Fig. 15. Beam propagation quality factor M² of combined QCL. (a) X axis; (b) Y axis

Download full size

Table 1. Performance parameters of long-wave infrared QCL
View table
Table 1. Performance parameters of long-wave infrared QCL
QCL centerwavelength /μm Fast axis waistradius /μm Slow axis waistradius /μm Fast axis divergencehalf-angle /（°）（1/e²） Slow axis divergencehalf-angle /（°）（1/e²）
7.8 4 4.5 34.73 30.64

Table 2. Lens data of point-source QCL collimator

View table

Table 2. Lens data of point-source QCL collimator

Surface	Radius of curvature	Semi-diameter /mm	Thickness /mm	Material	Conical coefficient	4th order term	6th order term	8th order term
1	$-$ 17.866	4.5	2.3	ZnSe	0	0	0	0
2	$-$ 5.060	4.5	—	—	$-$ 0.531	2.130×10^-5	2.181×10^-6	1.144×10^-9

Table 3. Lens data of extended-source QCL collimator

View table

Table 3. Lens data of extended-source QCL collimator

Surface	Radius of curvature	Semi-diameter /mm	Thickness /mm	Material	Conical coefficient	4th order term	6th order term
1	55.333	4.5	3	ZnSe	$-$ 1.616×10³⁶	1.329×10^-4	7.005×10^-7
2	$-$ 6.990	4.5	—	—	$-$ 0.276	4.593×10^-4	8.702×10^-6

Table 4. Lens data of QCL collimator with NA of 0.68

View table

Table 4. Lens data of QCL collimator with NA of 0.68

Surface	Radius of curvature	Semi-diameter /mm	Thickness /mm	Material	Conical coefficient	4th order term	6th order term
1	55.333	4.5	3	ZnSe	$-$ 1.616×10³⁶	1.329×10^-4	7.005×10^-7
2	$-$ 6.990	4.5	—	—	$-$ 0.276	4.593×10^-4	8.702×10^-6

Table 5. Lens data of QCL collimator with NA of 0.83

View table

Table 5. Lens data of QCL collimator with NA of 0.83

Surface	Radius of curvature	Semi-diameter /mm	Thickness /mm	Material	Conical coefficient	4th order term	6th order term
1	55.333	6	3	ZnSe	$-$ 1.994×10³⁶	$-$ 1.743×10^-5	$-$ 4.421×10^-7
2	$-$ 6.990	6	—	—	$-$ 0.276	4.480×10^-4	3.157×10^-6

Table 6. Lens data of fiber coupler
View table
Table 6. Lens data of fiber coupler
Surface Radius of curvature Semi-diameter /mm Thickness /mm Material Conical coefficient
1 209.0 12.7 4 ZnSe 0
2 Infinite 12.7 — — 0

Table 7. Measurement results of QCL output properties

View table

Table 7. Measurement results of QCL output properties

QCL ID	Output power /mW	Central wavelength /nm	Spectral linewidth /nm	Slow axis beamquality M²	Fast axis beam quality M²
1	472（@1.4 A）	7800	40	1.20	1.56
2	642（@0.8 A）	7830	85	1.22	1.55
3	621（@0.8 A）	7659	161	1.25	1.60
4	535（@1.4 A）	7728	226	1.23	1.50

Tools

Get Citation

Copy Citation Text

Meng Zhang, Xin Wang, Suhui Yang, Bao Li, Zhuo Li, Jinying Zhang, Yanze Gao. High-Efficiency Fiber Combining of Long-Wave Infrared Quantum Cascade Lasers[J]. Acta Optica Sinica, 2024, 44(8): 0814003

Download Citation

EndNote(RIS)BibTex Plain Text

Set citation alerts for article

Save article for my favorites