Functionalized diamond optomechanical circuits for infrared spectroscopy and site-specific gas sensing applications

• Applicants: Privatdozent Dr. Michael Hirtz; Professor Dr.-Ing. Christoph E. Nebel; Professor Dr. Wolfram Hans Peter Pernice
• Subject Area: Experimental Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2015 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 277599956

Diamond offers outstanding material properties paired with reliable processing techniques. The large bandgap, mechanical stability, large Youngs modulus, high thermal conductivity and chemical inertness make diamond a particularly attractive material for joined optical and mechanical applications. By employing chemical vapor deposition waferscale substrates can be prepared for reproducible and standardized device manufacture with industrial relevance. Taking advantage of recent progress in realizing large-scale optical circuits and on-chip nanomechanical resonators thus allows for leveraging both degrees of freedom in a unified technology. In this project diamond nanoscale devices will be employed for combined optical spectroscopy and mechanical sensing in the gase phase at infrared wavelengths. Exploiting optomechanical principles in integrated nanophotonic circuits provides a flexible platform in which both optical and mechanical resonators are coupled to photonic bus waveguides for parallel readout and multiplexing on chip. By moving towards a diamond platform, this proposal aims in particular at stretching the spectral operation range of optomechanical systems into the mid- / long-infrared wavelength regime. In order to achieve target specific sensors the optomechanical resonators will be functionalized using parallel dip-pen nanolithography (DPN). Through the nanometer resolution provided by DPN individual resonators will be prepared for site-specific mass-sensing, in order to enable the simultaneous readout of multiple analytes in a single device. Thus both qualitative analysis through optical spectroscopy and quantitative analysis based on nanomechanical sensing will enable fault-tolerant characterization with high sensitivity. The project therefore will lead to the establishment of a new material platform for broadband optical operation of photonic integrated circuits; it will extend the operation spectral range of current optomechanical devices far into the infrared; and the project will allow for implementing prototype optomechanical nose sensor arrays with potential for real-world applications.

• DFG Programme: Research Grants
• Major Instrumentation: Infrarotlaser
• Instrumentation Group: 5730 Spezielle Laser und -Stabilisierungsgeräte (Frequenz, Mode)