TY  - JOUR
A1  - Zink, Christof
A1  - Werner, Nils
A1  - Jechow, Andreas
A1  - Heuer, Axel
A1  - Menzel, Ralf
T1  - Multi-wavelength operation of a single broad area diode laser by spectral beam combining
JF  - IEEE photonics technology letters
N2  - Stabilized multi-wavelength emission from a single emitter broad area diode laser (BAL) is realized by utilizing an external cavity with a spectral beam combining architecture. Self-organized emitters that are equidistantly spaced across the slow axis are enforced by the spatially distributed wavelength selectivity of the external cavity. This resulted in an array like near-field emission although the BAL is physically a single emitter without any epitaxial sub-structuring and only one electrical contact. Each of the self-organized emitters is operated at a different wavelength and the emission is multiplexed into one spatial mode with near-diffraction limited beam quality. With this setup, multi-line emission of 31 individual spectral lines centered around and a total spectral width of 3.6 nm is realized with a 1000 mu m wide BAL just above threshold. To the best of our knowledge, this is the first demonstration of such a self-organization of emitters by optical feedback utilizing a spectral beam combining architecture.
KW  - Laser resonators
KW  - semiconductor lasers
KW  - optical feedback
Y1  - 2014
U6  - https://doi.org/10.1109/LPT.2013.2291963
SN  - 1041-1135
SN  - 1941-0174
VL  - 26
IS  - 3
SP  - 253
EP  - 256
PB  - Inst. of Electr. and Electronics Engineers
CY  - Piscataway
ER  - 
TY  - JOUR
A1  - Zink, Christof
A1  - Niebuhr, Mario
A1  - Jechow, Andreas
A1  - Heuer, Axel
A1  - Menzel, Ralf
T1  - Broad area diode laser with on-chip transverse Bragg grating stabilized in an off-axis external cavity
JF  - Optics express : the international electronic journal of optics
N2  - The emission characteristics of a novel, specially designed broad area diode laser (BAL) with on-chip transversal Bragg resonance (TBR) grating in lateral direction were investigated in an off-axis external cavity setup. The internal TBR grating defines a low loss transversal mode at a specific angle of incidence and a certain wavelength. By providing feedback at this specific angle with an external mirror, it is possible to select this low loss transverse mode and stabilize the BAL. Near diffraction limited emission with an almost single lobed far field pattern could be realized, in contrast to the double lobed far field pattern of similar setups using standard BALs or phase-locked diode laser arrays. Furthermore, we could achieve a narrow bandwidth emission with a simplified setup without external frequency selective elements. (C) 2014 Optical Society of America
Y1  - 2014
U6  - https://doi.org/10.1364/OE.22.014108
SN  - 1094-4087
VL  - 22
IS  - 12
SP  - 14108
EP  - 14113
PB  - Optical Society of America
CY  - Washington
ER  - 
TY  - JOUR
A1  - Schwarze, Thomas
A1  - Garz, Andreas
A1  - Teuchner, Klaus
A1  - Menzel, Ralf
A1  - Holdt, Hans-Jürgen
T1  - Two-photon probes for metal ions based on phenylaza[18]crown-6 ethers and 1,2,3-triazoles as pi-linkers
JF  - ChemPhysChem : a European journal of chemical physics and physical chemistry
KW  - absorption
KW  - cations
KW  - click chemistry
KW  - dyes/pigments
KW  - fluorescence
Y1  - 2014
U6  - https://doi.org/10.1002/cphc.201402232
SN  - 1439-4235
SN  - 1439-7641
VL  - 15
IS  - 12
SP  - 2436
EP  - 2439
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Heuer, Axel
A1  - Raabe, S.
A1  - Menzel, Ralf
T1  - Phase memory across two single-photon interferometers including wavelength conversion
JF  - Physical review : A, Atomic, molecular, and optical physics
N2  - Spontaneous parametric down-conversion (SPDC) in a nonlinear crystal generates two single photons (signal and idler) with random phases. Thus, no first-order interference between them occurs. However, coherence can be induced in a cascaded setup of two crystals if, e.g., the idler modes of both crystals are aligned to be indistinguishable. Due to the effect of phase memory it is found that the first-order interference of the signal beams can be controlled by the phase delay between the pump beams. Even for pump photon delays much larger than the coherence length of the SPDC photons, the visibility is above 90%. The high visibilities reported here prove an almost perfect phase memory effect across the two interferometers for the pump and the signal photon modes.
Y1  - 2014
U6  - https://doi.org/10.1103/PhysRevA.90.045803
SN  - 1050-2947
SN  - 1094-1622
VL  - 90
IS  - 4
PB  - American Physical Society
CY  - College Park
ER  -