Principle

The Joint Lab Quantum Photonic components develops hybrid micro-integration technologies to realize complex active (e.g. laser module) and passive (e.g. spectroscopy module) electro-optical modules. These modules meet stringent requirements for the deployment in the field or in space, which are

• compactness (small form factor) and small mass
• robustness and reliability (e.g. against environmental stress)
• extensive functionality at low system complexity (-> reliability)
• energy-efficiency
• high spectral and power stability
• for applications in space, space-compatibility has to be ensured for integration technologies, components and modules
  

For example, moving parts or high-outgassing materials cannot be used in hybrid micro-integration approaches.

• lithographically structured, printed circuit board-like, AlN-ceramic module body for the micro-integration of electrical, electro-optical and optical components
• beam shaping via micro-optical components on the module body
• design and development of special components (e.g. micro-lenses, fiber couplers, optical isolators, micro-thermoelectric coolers, isolated coaxial feedthroughs)
• hermetic housing concept with integrated, HF-compatible, electrical and fiber-based optical feedthroughs
• simultaneous active micro-assembly of several optical components with robots providing ultra-high spatial resolution; parameters like beam pointing, beam profile, output power, and spectral properties are recorded and optimized during alignment and assembly
• implementation of all integration processes with space-compatible technologies, if possible
• development of methods that allow for flexible automation of assembly tasks

• micro-integration: robots provide
  • spatial resolution of 1 nm
  • angular resolution of  1 µrad
• modules:
  
  • integration of active components (e.g. laser diodes) and passive optical components (e.g. phase modulators, wave guides)
  • typical wavelength:  630 nm ... 1120 nm directly with GaAs-based laser chips, VIS and UV ranges via non-linear frequency conversion
  • typical form factor : up to 130 x 80 x 25 mm³
  • typical masses: 50 g ... 750 g depending on model
  • resilience to mechanical stress typically according to ESCC Basic Specification Nr. 91 (ESA Evaluation Test Programme For Laser Diodes)
  • resilience to thermal cycling according to ESCC Basic Specification Nr. 91 (ESA Evaluation Test Programme For Laser Diodes)
  • poster Technology and poster Laser Modules

Micro-integration of laser systems, of systems for non-linear frequency conversion and of spectroscopy modules

• for precision spectroscopy experiments in space, e.g. for atom interferometry with ultra-cold Rubidium and Potassium quantum gases. [R01,R02, R03, R04, R05, R06, R07]
• for portable optical atomic clocks [R08, R09, R10]
• for satellite-based distance measurements with lasers [R11]
• for coherent communication [R12, R13]

• R01      D. Becker et al., Space-borne Bose–Einstein condensation for precision inter-ferometry, Nature 562 (2018), 391-395
• R02      A. N. Dinkelaker et al., Autonomous frequency stabilization of two extended-cavity diode lasers at the potassium wavelength on a sounding rocket, Appl. Opt. 56 (2017), 1388-1396
• R03      M. Lezius et al., Space-borne frequency comb metrology, Optica 3, (2016), 1381-1387
• R04      Th. Schuldt et al., Design of a dual species atom interferometer for space, Exp Astron 39 (2015), 167–206
• R05      D. Aguilera et al., STE-QUEST - Test of the universality of free fall using cold atom interferometry, Class. Quantum Grav. 31, (2014) 115010
• R06      H. Müntinga et al., Interferometry with Bose-Einstein condensates in microgravity, Phys. Rev. Lett. 110, (2013) 093602
• R07      T. Van Zoest et al., Bose-Einstein Condensation in Microgravity, Science 238, (2010), pp. 1540-1543
• R08      A. D. Ludlow et al., Optical atomic clocks, Rev. Mod. Phys. 87, (2015) 637
• R09      K. Bongs et al., Development of a strontium optical lattice clock for the SOC mission on the ISS, C. R. Phys. 16, (2015) 553
• R10      K. Bongs, M. Holynski, and Y. Singh, Ψ in the sky, Nat. Phys. 11, (2015) 615
• R11      B. S. Sheard et al., Intersatellite laser ranging instrument for the GRACE follow-on mission, J. Geod. 86, (2012) 1083
• R12      F. Heine et al., Optical Inter-Satellite Communication Operational, MILCOM (2010), 1583-1587
• R13      S. Seel et al., Alphasat laser terminal commissioning status aiming to demonstrate Geo-Relay for Sentinel SAR and optical sensor data. IGARSS (2014), 100-101