title: Study of QCL Laser Sources for the Realization of Advanced Sensors.
abstract: We study the nonlinear dynamics of a quantum cascade laser (QCL) with a strong reinjection provided by the feedback from two external targets in a double cavity configuration. The nonlinear coupling of interferometric signals from the two targets allows us to propose a displacement sensor with nanometric resolution. The system exploits the ultra-stability of QCLs in self-mixing configuration to access the intrinsic nonlinearity of the laser, described by the Lang-Kobayashi model, and it relies on a stroboscopic-like effect in the voltage signal registered at the QCL terminals that relates the "slow" target motion to the "fast" target one.
authors.affiliation: Dipartimento Interareneo di Fisica, Università degli Studi e Politecnico di Bari, via Amendola 173, I-70126 Bari, Italy. giuseppe.derisi@gmail.com.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: de Risi
authors.affiliation: Dipartimento Interareneo di Fisica, Università degli Studi e Politecnico di Bari, via Amendola 173, I-70126 Bari, Italy. lorenzo.columbo@uniba.it.|CNR-Istituto di Fotonica e Nanotecnologie UOS Bari, via Amendola 173, I-70126 Bari, Italy. lorenzo.columbo@uniba.it.
authors.forename: Lorenzo Luigi
authors.initials: LL
authors.lastname: Columbo
authors.affiliation: Dipartimento Interareneo di Fisica, Università degli Studi e Politecnico di Bari, via Amendola 173, I-70126 Bari, Italy. massimo.brambilla@uniba.it.|CNR-Istituto di Fotonica e Nanotecnologie UOS Bari, via Amendola 173, I-70126 Bari, Italy. massimo.brambilla@uniba.it.
authors.forename: Massimo
authors.initials: M
authors.lastname: Brambilla
keywords: laser sensors; nano displacement sensing; optical feedback interferometry; quantum cascade laser