Hybrid Micro-Integration Technology

Principle

The Joint Lab Laser Metrology 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-compatible components and technologies need to be integrated and implemented, respectively

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

  • integration
    [+] Integration setup with four movable objects in 6 axes
  • integration
    [+] Integration of laser module
  • MOPA detail
    [+] DFB diode with collimation optics and isolator on laser module
  • ECDL details
    [+] Grating on micro-peltier element on laser module
  • HF feedthrough
    [+] Electrical HF feedthrough for micro-modules
  • Optical feedthrough
    [+] Optical feedthrough for micro-modules
  • Lens
    [+] Micro-lens as integrated in our laser modules
  • TEC
    [+] Micro-peltier element as integrated in our ECDL modules

Assembly technology

  • AlN-ceramic-based, galvanically structured 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. mico-lenses, micro-thermoelectric coolers, isolated coaxial feedthroughs)
  • hermetic housing concept with integrated, HF-compatible, electrical feedthroughs and with 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

Typical features

  • micro-integration:
    • robots provides spatial resolutions of 1 nm
    • robots provides angle  resolutions 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

Applications

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. [R02, R03, R04, R05]
  • for portable optical atomic clocks [R06, R07, R08]
  • for satellite-based distance measurements with lasers [R09]
  • for coherent communication [R10, R11]

Related Publications

  • R02      Th. Schuldt et al., Design of a dual species atom interferometer for space, Exp Astron 39 (2015), 167–206
  • R03      D. Aguilera et al., STE-QUEST - Test of the universality of free fall using cold atom interferometry, Class. Quantum Grav. 31, (2014) 115010
  • R04      H. Müntinga et al., Interferometry with Bose-Einstein condensates in microgravity, Phys. Rev. Lett. 110, (2013) 093602
  • R05      T. Van Zoest et al., Bose-Einstein Condensation in Microgravity, Science 238, (2010), pp. 1540-1543
  • R06      A. D. Ludlow et al., Optical atomic clocks, Rev. Mod. Phys. 87, (2015) 637
  • R07      K. Bongs et al., Development of a strontium optical lattice clock for the SOC mission on the ISS, C. R. Phys. 16, (2015) 553
  • R08      K. Bongs, M. Holynski, and Y. Singh, Ψ in the sky, Nat. Phys. 11, (2015) 615
  • R09      B. S. Sheard et al., Intersatellite laser ranging instrument for the GRACE follow-on mission, J. Geod. 86, (2012) 1083
  • R10      F. Heine et al., Optical Inter-Satellite Communication Operational, MILCOM (2010), 1583-1587
  • R11      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