Dr. Dan Dalacu Profile

Dr. Dan Dalacu

at National Research Council Canada

SPIE Involvement:

Author

Publications (18)

Proceedings Article | 13 March 2024 Presentation + Paper

Assorted experiments with atoms in hollow-core fibers

Rubayet Al Maruf, Paul Anderson, Sai Sreesh Venuturumilli, Michael Li, Katie McDonnell, Philip Poole, Dan Dalacu, Michael Reimer, Michal Bajcsy

Proceedings Volume 12912, 1291208 (2024) https://doi.org/10.1117/12.3012387

KEYWORDS: Chemical species, Cesium, Quantum dot emission, Pulse signals, Quantum experiments, Quantum dots, Pulsed laser operation, Clouds, Quantum optics experiments, Quantum numbers, Hollow waveguides

Read Abstract +

Proceedings Article | 19 July 2023 Presentation

Implementation of a universal fine-structure eraser for quantum dots

Maeve Wentland, Sonell Malik, Andreas Fognini, Val Zwiller, Dan Dalacu, Philip Poole, Michael Reimer

Proceedings Volume PC12633, PC126330N (2023) https://doi.org/10.1117/12.2673257

KEYWORDS: Semiconductor quantum dots, Photons, Quantum entanglement, Quantum sources, Waveguides, Quantum information, Quantum frequencies, Quantum dots, Excitons, Electro optics

Read Abstract +

Proceedings Article | 19 July 2023 Presentation

Observing near-unity entanglement from an indium-rich nanowire quantum dot

Matteo Pennacchietti, Mohd Zeeshan, Brady Cunard, Philip Poole, Dan Dalacu, Andreas Fognini, Klaus Jöns, Val Zwiller, Michael Reimer

Proceedings Volume PC12633, PC126330M (2023) https://doi.org/10.1117/12.2672966

KEYWORDS: Quantum entanglement, Nanowires, Quantum dots, Quantum limits, Quantum information, Quantum experiments, Temporal resolution, Solid state physics, Single photon detectors, Semiconductor quantum dots

Read Abstract +

Proceedings Article | 15 March 2023 Presentation + Paper

Hybrid quantum photonic integrated circuits

Khaled Mnaymneh, Edith Yeung, David Northeast, Jeongwan Jin, Patrick Laferrière, Sofiane Haffouz, Robin Williams, Philip Poole, Dan Dalacu

Proceedings Volume 12430, 1243008 (2023) https://doi.org/10.1117/12.2648995

KEYWORDS: Quantum sources, Quantum emitters, Photonic integrated circuits, Nanowires, Waveguides, Quantum processes, Quantum photonics, Quantum enhancement, Photons, Integrated circuits

Read Abstract +

Proceedings Article | 3 March 2022 Presentation + Paper

Single-photon source based on a quantum dot emitting at cesium wavelength

Rubayet Al Maruf, Sai Sreesh Venuturumilli, Divya Bharadwaj, Paul Anderson, Jiawei Qiu, Yujia Yuan, Behrooz Semnani, Sonell Malik, Mohd Zeeshan, Dan Dalacu, Philip Poole, Michael Reimer, Michal Bajcsy

Proceedings Volume 12016, 1201611 (2022) https://doi.org/10.1117/12.2616977

KEYWORDS: Photons, Nanowires, GRIN lenses, Cesium, Quantum dots, Single mode fibers, Structured optical fibers, Satellites, Semiconductors, Wavelength tuning

Read Abstract +

Proceedings Article | 8 March 2021 Presentation + Paper

Interfacing quantum dots with laser-cooled atomic ensembles

Divya Bharadwaj, Paul Anderson, Sreesh Venuturumilli, Rubayet Al Maruf, Jiawei Qiu, Taehyun Yoon, Behrooz Semnani, Yujia Yuan, Jinjin Du, Mohd Zeeshan, Philip Poole, Dan Dalacu, Michael Reimer, Michal Bajcsy

Proceedings Volume 11700, 117003Z (2021) https://doi.org/10.1117/12.2586902

KEYWORDS: Quantum dots, Semiconductor lasers, Photons, Single photon, Semiconductors, Satellites, Optical fibers, Nanowires, Fiber lasers, Chemical species

Read Abstract +

Proceedings Article | 25 September 2017 Presentation

On-chip hybrid quantum circuits (Conference Presentation)

Klaus Jöns, Ali Elshaari, Iman Esmaeil Zadeh, Andreas Fognini, Michael Reimer, Dan Dalacu, Philip Poole, Val Zwiller

Proceedings Volume 10358, 103580R (2017) https://doi.org/10.1117/12.2271680

KEYWORDS: Optical filters, Photonic integrated circuits, Quantum circuits, Quantum dots, Semiconductors, Silicon photonics, Nanofabrication, Resonators, Photonic devices, Quantum communications

Read Abstract +

Proceedings Article | 14 March 2013 Paper

Bright single-photon sources based on self-aligned quantum dots in tapered nanowire waveguides

Michael Reimer, Gabriele Bulgarini, Erik P.A.M. Bakkers, Dan Dalacu, Philip Poole, Val Zwiller

Proceedings Volume 8619, 861903 (2013) https://doi.org/10.1117/12.2008717

KEYWORDS: Quantum dots, Waveguides, Quantum efficiency, Gold, Mirrors, Excitons, Quantum communications, Waveguide modes, Dielectrics, Nanowires

Read Abstract +

Proceedings Article | 5 March 2013 Paper

III-V access waveguides using atomic layer deposition

Khaled Mnaymneh, Simon Frédérick, Dan Dalacu, Jean Lapointe, Philip Poole, Robin Williams

Proceedings Volume 8613, 86130D (2013) https://doi.org/10.1117/12.2004310

KEYWORDS: Waveguides, Photonics, Atomic layer deposition, Compound semiconductors, Active optics, Integrated optics, Photonic crystals, Refractive index, Nanostructures, Quantum dots

Read Abstract +

Proceedings Article | 1 March 2011 Paper

Positioned growth of InP nanowires

P. J. Poole, D. Dalacu, J. Lapointe, A. Kam, K. Mnaymneh

Proceedings Volume 7947, 79470K (2011) https://doi.org/10.1117/12.876196

KEYWORDS: Gold, Particles, Silica, Quantum dots, Photomasks, Interfaces, Heterojunctions, Oxides, Semiconducting wafers, Nanowires

Read Abstract +

Proceedings Article | 10 February 2011 Paper

Spectral tuning of site-selected single InAs/InP quantum dots via intermixing

K. Mnaymneh, D. Dalacu, P. Poole, J. Lapointe, R. Cheriton, R. Williams

Proceedings Volume 7947, 794704 (2011) https://doi.org/10.1117/12.875634

KEYWORDS: Quantum dots, Polarization, Excitons, Oxides, Silica, Indium arsenide, Photomasks, Annealing, Semiconducting wafers, Nanoengineering

Read Abstract +

Proceedings Article | 23 January 2010 Paper

Scalable routes to single and entangled photon pair sources: tailored InAs/InP quantum dots in photonic crystal microcavities

Dan Dalacu, Khaled Mnaymneh, Vera Sazonova, Philip Poole, Geof Aers, Ross Cheriton, Mike Reimer, Jean Lapointe, Pawel Hawrylak, Marek Korkusiński, Eugene Kadantsev, Robin Williams

Proceedings Volume 7608, 76082G (2010) https://doi.org/10.1117/12.846729

KEYWORDS: Quantum dots, Photonic crystals, Oxides, Silica, Optical microcavities, Semiconductors, Process control, Control systems, Oxidation, Directed self assembly

Read Abstract +

Proceedings Article | 24 February 2009 Paper

Deterministic coupling of site-selected InAs/InP quantum dots to 2D photonic crystal microcavities

Dan Dalacu, Danny Kim, Simon Frédérick, Jean Lapointe, Anthony Springthorpe, Philip Poole, Geof Aers, Robin Williams

Proceedings Volume 7211, 72110H (2009) https://doi.org/10.1117/12.816143

KEYWORDS: Quantum dots, Photonic crystals, Epitaxy, Optical alignment, Optical microcavities, Electron beam lithography, Indium arsenide, Quantum information, Indium gallium arsenide, Silica

Read Abstract +

Proceedings Article | 1 March 2006 Paper

Monolithically integrated graded-index waveguide input couplers for silicon-photonics

S. Janz, A. Delage, B. Lamontagne, A. Bogdanov, D. Dalacu, D.-X. Xu, K.P. Yap

Proceedings Volume 6125, 61250M (2006) https://doi.org/10.1117/12.648750

KEYWORDS: Waveguides, GRIN lenses, Silicon, Amorphous silicon, Waveguide modes, Polarization, Refractive index, Tolerancing, Wave propagation, Etching

Read Abstract +

Proceedings Article | 1 March 2006 Paper

Second-order nonlinear mixing of two modes in a planar photonic crystal microcavity

Murray McCutcheon, Jeff Young, Georg Rieger, Dan Dalacu, Simon Frédérick, Philip Poole, Geof Aers, Robin Williams

Proceedings Volume 6128, 612812 (2006) https://doi.org/10.1117/12.647006

KEYWORDS: Polarization, Optical microcavities, Photonic crystals, Spectroscopy, Quantum dots, Finite-difference time-domain method, Second-harmonic generation, Scattering, Laser scattering, Nonlinear optics

Read Abstract +

Proceedings Article | 7 March 2005 Paper

Design of polarization-insensitive components using geometrical and stress-induced birefringence in SOI waveguides

Dan-Xia Xu, Winnie Ye, Alexei Bogdanov, Dan Dalacu, Andre Delage, Pavel Cheben, Siegfried Janz, Boris Lamontagne, Marie-Josee Picard

Proceedings Volume 5730, (2005) https://doi.org/10.1117/12.589158

KEYWORDS: Waveguides, Birefringence, Cladding, Oxides, Silicon, Etching, Polarization, Wave propagation, Refractive index, Solids

Read Abstract +

We review the use of the oxide cladding stress induced photoelastic effect to eliminate the modal birefringence in silicon-on-insulator (SOI) ridge waveguide components, and highlight characteristics particular to high index contrast (HIC) systems. The birefringence in planar waveguides has its origin in the electromagnetic boundary conditions at the waveguide boundaries, and can be further modified by the presence of stress in the materials. It is shown that geometrical constraints imposed by different design and fabrication considerations become increasingly difficult to satisfy with decreasing core sizes. On the other hand, with typical stress levels of -100 MPa to -400 MPa (compressive) in SiO₂ used as the upper cladding, the effective indices are altered up to the order of 10^-3 for ridges with heights ranging from 1 μm to 5 μm. We demonstrate that the stress can be effectively used to balance the geometrical birefringence. Birefringence-free operation is achieved for waveguides with otherwise large birefringence by using properly chosen thickness and stress of the upper cladding layer. This allows the waveguide cross-section profiles to be optimized for design criteria other than zero-birefringence. Since the index changes induced by the stress are orders of magnitude smaller than the waveguide core/cladding index contrast, changes in the mode profiles are insignificant and the associated mode mismatch loss is negligible. We study the stress-induced effects in two parallel waveguides of varying spacing, to emulate the condition in directional couplers and ring-resonators. In the arrayed waveguide grating (AWG) demultiplexers fabricated in the SOI platform, we demonstrated the reduction of the birefringence from 1.3x10^-3 (without the upper cladding) to below 1x10^-4 across the spectral band by using a 0.6 μm oxide upper cladding with a stress of -320 MPa (compressive). Design options for relaxed dimensional tolerance and improved coupler performance made available by using stress engineering are discussed.

Proceedings Article | 20 December 2004 Paper

Graded-index coupler for microphotonic SOI waveguides

Andre Delage, Siegfried Janz, Dan Xu, Dan Dalacu, Boris Lamontagne, Alexei Bogdanov

Proceedings Volume 5577, (2004) https://doi.org/10.1117/12.567264

KEYWORDS: Waveguides, GRIN lenses, Silicon, Plasma enhanced chemical vapor deposition, Optical components, Optical networks, Integrated optics, Photonics, Photonic crystal devices, Refractive index

Read Abstract +

Proceedings Article | 30 May 2003 Paper

Birefringence compensation in silicon-on-insulator planar waveguide demultiplexers using a buried oxide layer

Pavel Cheben, Dan-Xia Xu, Siegfried Janz, Andre Delage, Dan Dalacu

Proceedings Volume 4997, (2003) https://doi.org/10.1117/12.476661

KEYWORDS: Waveguides, Birefringence, Polarization, Amorphous silicon, Silicon, Demultiplexers, Oxides, Refractive index, Planar waveguides, Etching

Read Abstract +

The high index contrast of silicon-on-insulator (SOI) enables the scaling down of planar waveguide components into the microphotonic regime, but has the unwanted consequence of inducing a large TE-TM polarization birefringence. For ridge waveguides this birefringence can be reduced to an acceptable level by using appropriate ridge dimensions [1], but with decreasing Si thickness the required fabrication tolerances quickly become too narrow to implement this solution. Components with slab waveguide regions such as echelle grating demultiplexers cannot be made polarization independent using this method. An alternate approach is to introduce a polarization compensation region in the combiner section of an AWG or echelle grating to eliminate the polarization dependent wavelength shift[2]. In its original implementation, the compensator is fabricated by changing the local waveguide thickness. The resulting birefringence correction can be sensitive to errors in etch depth, and the mode mismatch between compensator and slab waveguide sections is a source of approximately 1 dB extra insertion loss (IL) for SOI demultiplexers with Si waveguide thickness in the range from 2 to 5 m. We describe a new compensator structure for the SOI platform using a buried low index layer, in this case SiO2 sandwiched between the Si waveguide layer and another Si cap layer. Such a silicon-oxide-silicon (SOS) compensator on SOI can eliminate the TE-TM wavelength shift of an SOI AWG or echelle grating demultiplexer without introducing a significant mode mismatch between the compensator and slab waveguide sections. A demultiplexer with an SOS compensator has almost 1 dB lower insertion loss of an equivalent device with an etched compensator. The SOS compensator is easily implemented using standard oxide and a-Si or polysilicon deposition techniques. In this paper we present calculations and experimental results on the effective birefringence compensation, PDL and IL of SOS compensators in SOI waveguide demultiplexers.

Showing 5 of 18 publications

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years