Martijn Heck - Academia.edu (original) (raw)

Papers by Martijn Heck

We present results on modal gain measurements in InAs/InGaAsP/InP quantum dot amplifiers in the 1... more We present results on modal gain measurements in InAs/InGaAsP/InP quantum dot amplifiers in the 1600nm to 1800nm wavelength range. A modified gain measurement technique was used to determine the gain at different injection current densities. The modal gain is determined by measuring the amplified spontaneous emission (ASE) power from a series of two-section Fabry-Perot ridge waveguides with variable amplifier section lengths. The results show that this material can be used for tunable lasers with a tuning range of at least 100nm.

We report on the design and fabrication of tunable integrated pulse shaping devices. These device... more We report on the design and fabrication of tunable integrated pulse shaping devices. These devices are realized in the InP/InGaAsP material system and contain an arrayed waveguide grating pair and an array of phase modulators. An arbitrary discrete phase profile can be applied to a pulse propagating through the pulse shaper. The bandwidth of the pulse shaper and the AWG channel spacing are chosen to be able to compress chirped picosecond pulses down to 300fs. Further integration with a modelocked laser source then allows for the realization of a femtosecond pulse source. Different geometries for the device are presented.

Integrated modelocked lasers producing pulses down to 2.1 ps were fabricated in bulk In-GaAsP usi... more Integrated modelocked lasers producing pulses down to 2.1 ps were fabricated in bulk In-GaAsP using butt-joint active-passive integration. It is demonstrated that good modelocked operation can be obtained in devices using this integration technology. Pulses obtained are close to transform limited and the dynamics outside the control parameter range for modelocked operating are reduced through the use of an extended cavity.

Optical Fiber Communication Conference, 2014

ABSTRACT An integrated delay line coupled cavity was used to stabilize a 10 GHz mode locked laser... more ABSTRACT An integrated delay line coupled cavity was used to stabilize a 10 GHz mode locked laser. Use of the cavity reduced the RF 3 dB linewidth for passive mode-locking from 1.06 MHz to 15 kHz.

Optical Fiber Communication Conference, 2014

ABSTRACT We present results from two hybrid silicon mode-locked lasers each with a 2GHz cavity an... more ABSTRACT We present results from two hybrid silicon mode-locked lasers each with a 2GHz cavity and one with an intra-cavity filter; which allows for 20GHz operation and 55dB supermode noise suppression compared to harmonic mode-locking.

Optics Express, 2015

We present the design of a novel platform that is able to combine optical frequency bands spannin... more We present the design of a novel platform that is able to combine optical frequency bands spanning 4.2 octaves from ultraviolet to mid-wave infrared into a single, low M 2 output waveguide. We present the design and realization of a key component in this platform that combines the wavelength bands of 350 nm -1500 nm and 1500 nm -6500 nm with demonstrated efficiency greater than 90% in near-infrared and mid-wave infrared. The multi-octave spectral beam combiner concept is realized using an integrated platform with silicon nitride waveguides and silicon waveguides. Simulated bandwidth is shown to be over four octaves, and measured bandwidth is shown over two octaves, limited by the availability of sources.

IEEE Photonic Society 24th Annual Meeting, 2011

An optical phased array for free-space beam control is proposed, designed, and fabricated by inte... more An optical phased array for free-space beam control is proposed, designed, and fabricated by integration of surface gratings and phase tuners within a waveguide array. Two methods of characterizing the beam are demonstrated to measure the wavelength-dependent emission versus duty cycle and width.

Silicon Photonics VIII, 2013

ABSTRACT Free-space beam steering using optical phase arrays are desirable as a means of implemen... more ABSTRACT Free-space beam steering using optical phase arrays are desirable as a means of implementing Light Detection and Ranging (LIDAR) and free-space communication links without the need for moving parts, thus alleviating vulnerabilities due to vibrations and inertial forces. Implementing such an approach in silicon photonic integrated circuits is particularly desirable in order to take advantage of established CMOS processing techniques while reducing both device size and packaging complexity. In this work we demonstrate a free-space diode laser together with beam steering implemented on-chip in a silicon photonic circuit. A waveguide phased array, surface gratings, a hybrid III-V/silicon laser and an array of hybrid III/V silicon amplifiers were fabricated on-chip in order to achieve a fully integrated steerable free-space optical source with no external optical inputs, thus eliminating the need for fiber coupling altogether. The chip was fabricated using a modified version of the hybrid silicon process developed at UCSB, with modifications in order to incorporate diodes within the waveguide layer as well as within the III-V gain layer. Beam steering across a 12° field of view with +/-0.3° accuracy and 1.8°x0.6° beam width was achieved, with background peaks suppressed 7 dB relative to the main lobe within the field of view for arbitrarily chosen beam directions.

IEEE Photonics Conference 2012, 2012

We demonstrate an integrated silicon and ultra-low-loss silica waveguide platform. Coupling betwe... more We demonstrate an integrated silicon and ultra-low-loss silica waveguide platform. Coupling between layers is achieved with (0.4±0.2) dB of loss per transition and a 20 nm 3-dB bandwidth.

We demonstrate the feasibility of using a hybrid silicon mode-locked laser in a coupled optoelect... more We demonstrate the feasibility of using a hybrid silicon mode-locked laser in a coupled optoelectronic oscillator configuration for generating low phase noise 20 GHz microwave signal. The free-running oscillator has a 3dB RF linewidth of 14kHz.

Optical Fiber Communication Conference, 2012

We compare ultra-low-loss silica waveguides with PECVD SiO 2 , borophosphosilicate glass (BPSG), ... more We compare ultra-low-loss silica waveguides with PECVD SiO 2 , borophosphosilicate glass (BPSG), and wafer-bonded thermal oxide upper claddings. We demonstrate fiber-like (0.045 dB/m) total propagation loss in planar waveguides with bonded thermal oxide upper claddings.

Advanced Photonics Congress, 2012

A technique for making high extinction and broadband polarizers in a low loss planar waveguide pl... more A technique for making high extinction and broadband polarizers in a low loss planar waveguide platform is presented and characterized. Extinction greater than 78 dB is obtained with low loss for the desired polarization.

Applied Physics A, 2014

Planar waveguides with ultra-low propagation loss are necessary for integrating optoelectronic sy... more Planar waveguides with ultra-low propagation loss are necessary for integrating optoelectronic systems that require long optical time delay or narrowband optical filters. In this paper, we review an ultra-low loss planar waveguide platform that uses thin (\150 nm) Si 3 N 4 cores and thick ([8 lm) SiO 2 cladding layers. In particular, we discuss the performance of arrayed waveguide gratings (AWGs) fabricated with the platform. We propose the use of a practical design method that takes the statistical nature of worst-case crosstalk into account. We also demonstrate the measurement of amplitude and phase error distributions in an AWG using an optical backscatter reflectometer. We show that the waveguides have phase errors small enough to achieve AWG crosstalk below -30 dB, while crosstalk below -40 dB should also be possible with optimization of the component design.

22nd IEEE International Semiconductor Laser Conference, 2010

For the first time, a fully integrated hybrid silicon AWG based multiwavelength laser on SOI is p... more For the first time, a fully integrated hybrid silicon AWG based multiwavelength laser on SOI is presented. Four-channel operation with 360 GHz spacing and 25-35 dB SMSR is shown.

IEEE Photonics Conference 2012, 2012

ABSTRACT An optical 2R regenerator is presented. The device consists of an optical amplifier inte... more ABSTRACT An optical 2R regenerator is presented. The device consists of an optical amplifier integrated with a saturable absorber. Over 3 dB improvement in the extinction ratio is seen for 1 Gb/s signals at 1560 nm.

Silicon Photonics VI, 2011

ABSTRACT We present our work on fully integrated hybrid silicon optical buffers capable of holdin... more ABSTRACT We present our work on fully integrated hybrid silicon optical buffers capable of holding 40 byte packets at 40 Gb/s. These devices consist of low loss silicon waveguides and cascaded amplifiers to overcome passive losses in a 1.1 m long delay line. Since cascading multiple gain elements leads to ASE (noise) accumulation, reshaping elements in the form of saturable absorbers are integrated in the delay. Noise filtering in the buffer is investigated by simulating the eye diagram for a delay line with 1R regenerators and comparing it to that of a 2R regenerator. Finally, preliminary experimental data from the optical buffer is shown.

Smart Photonic and Optoelectronic Integrated Circuits XVI, 2014

ABSTRACT Free-space beam steering using optical phased arrays is a promising method for implement... more ABSTRACT Free-space beam steering using optical phased arrays is a promising method for implementing free-space communication links and Light Detection and Ranging (LIDAR) without the sensitivity to inertial forces and long latencies which characterize moving parts. Implementing this approach on a silicon-based photonic integrated circuit adds the additional advantage of working with highly developed CMOS processing techniques. In this work we discuss our progress in the development of a fully integrated 32 channel PIC with a widely tunable diode laser, a waveguide phased array, an array of fast phase modulators, an array of hybrid III-V/silicon amplifiers, surface gratings, and a graded index lens (GRIN) feeding an array of photodiodes for feedback control. The PIC has been designed to provide beam steering across a 15°x5° field of view with 0.6°x0.6° beam width and background peaks suppressed 15 dB relative to the main lobe within the field of view for arbitrarily chosen beam directions. Fabrication follows the hybrid silicon process developed at UCSB with modifications to incorporate silicon diodes and a GRIN lens.

We present results on modal gain measurements in InAs/InGaAsP/InP quantum dot amplifiers in the 1... more We present results on modal gain measurements in InAs/InGaAsP/InP quantum dot amplifiers in the 1600nm to 1800nm wavelength range. A modified gain measurement technique was used to determine the gain at different injection current densities. The modal gain is determined by measuring the amplified spontaneous emission (ASE) power from a series of two-section Fabry-Perot ridge waveguides with variable amplifier section lengths. The results show that this material can be used for tunable lasers with a tuning range of at least 100nm.

We report on the design and fabrication of tunable integrated pulse shaping devices. These device... more We report on the design and fabrication of tunable integrated pulse shaping devices. These devices are realized in the InP/InGaAsP material system and contain an arrayed waveguide grating pair and an array of phase modulators. An arbitrary discrete phase profile can be applied to a pulse propagating through the pulse shaper. The bandwidth of the pulse shaper and the AWG channel spacing are chosen to be able to compress chirped picosecond pulses down to 300fs. Further integration with a modelocked laser source then allows for the realization of a femtosecond pulse source. Different geometries for the device are presented.

Integrated modelocked lasers producing pulses down to 2.1 ps were fabricated in bulk In-GaAsP usi... more Integrated modelocked lasers producing pulses down to 2.1 ps were fabricated in bulk In-GaAsP using butt-joint active-passive integration. It is demonstrated that good modelocked operation can be obtained in devices using this integration technology. Pulses obtained are close to transform limited and the dynamics outside the control parameter range for modelocked operating are reduced through the use of an extended cavity.

Optical Fiber Communication Conference, 2014

ABSTRACT An integrated delay line coupled cavity was used to stabilize a 10 GHz mode locked laser... more ABSTRACT An integrated delay line coupled cavity was used to stabilize a 10 GHz mode locked laser. Use of the cavity reduced the RF 3 dB linewidth for passive mode-locking from 1.06 MHz to 15 kHz.

Optical Fiber Communication Conference, 2014

ABSTRACT We present results from two hybrid silicon mode-locked lasers each with a 2GHz cavity an... more ABSTRACT We present results from two hybrid silicon mode-locked lasers each with a 2GHz cavity and one with an intra-cavity filter; which allows for 20GHz operation and 55dB supermode noise suppression compared to harmonic mode-locking.

Optics Express, 2015

We present the design of a novel platform that is able to combine optical frequency bands spannin... more We present the design of a novel platform that is able to combine optical frequency bands spanning 4.2 octaves from ultraviolet to mid-wave infrared into a single, low M 2 output waveguide. We present the design and realization of a key component in this platform that combines the wavelength bands of 350 nm -1500 nm and 1500 nm -6500 nm with demonstrated efficiency greater than 90% in near-infrared and mid-wave infrared. The multi-octave spectral beam combiner concept is realized using an integrated platform with silicon nitride waveguides and silicon waveguides. Simulated bandwidth is shown to be over four octaves, and measured bandwidth is shown over two octaves, limited by the availability of sources.

IEEE Photonic Society 24th Annual Meeting, 2011

An optical phased array for free-space beam control is proposed, designed, and fabricated by inte... more An optical phased array for free-space beam control is proposed, designed, and fabricated by integration of surface gratings and phase tuners within a waveguide array. Two methods of characterizing the beam are demonstrated to measure the wavelength-dependent emission versus duty cycle and width.

Silicon Photonics VIII, 2013

ABSTRACT Free-space beam steering using optical phase arrays are desirable as a means of implemen... more ABSTRACT Free-space beam steering using optical phase arrays are desirable as a means of implementing Light Detection and Ranging (LIDAR) and free-space communication links without the need for moving parts, thus alleviating vulnerabilities due to vibrations and inertial forces. Implementing such an approach in silicon photonic integrated circuits is particularly desirable in order to take advantage of established CMOS processing techniques while reducing both device size and packaging complexity. In this work we demonstrate a free-space diode laser together with beam steering implemented on-chip in a silicon photonic circuit. A waveguide phased array, surface gratings, a hybrid III-V/silicon laser and an array of hybrid III/V silicon amplifiers were fabricated on-chip in order to achieve a fully integrated steerable free-space optical source with no external optical inputs, thus eliminating the need for fiber coupling altogether. The chip was fabricated using a modified version of the hybrid silicon process developed at UCSB, with modifications in order to incorporate diodes within the waveguide layer as well as within the III-V gain layer. Beam steering across a 12° field of view with +/-0.3° accuracy and 1.8°x0.6° beam width was achieved, with background peaks suppressed 7 dB relative to the main lobe within the field of view for arbitrarily chosen beam directions.

IEEE Photonics Conference 2012, 2012

We demonstrate an integrated silicon and ultra-low-loss silica waveguide platform. Coupling betwe... more We demonstrate an integrated silicon and ultra-low-loss silica waveguide platform. Coupling between layers is achieved with (0.4±0.2) dB of loss per transition and a 20 nm 3-dB bandwidth.

We demonstrate the feasibility of using a hybrid silicon mode-locked laser in a coupled optoelect... more We demonstrate the feasibility of using a hybrid silicon mode-locked laser in a coupled optoelectronic oscillator configuration for generating low phase noise 20 GHz microwave signal. The free-running oscillator has a 3dB RF linewidth of 14kHz.

Optical Fiber Communication Conference, 2012

We compare ultra-low-loss silica waveguides with PECVD SiO 2 , borophosphosilicate glass (BPSG), ... more We compare ultra-low-loss silica waveguides with PECVD SiO 2 , borophosphosilicate glass (BPSG), and wafer-bonded thermal oxide upper claddings. We demonstrate fiber-like (0.045 dB/m) total propagation loss in planar waveguides with bonded thermal oxide upper claddings.

Advanced Photonics Congress, 2012

A technique for making high extinction and broadband polarizers in a low loss planar waveguide pl... more A technique for making high extinction and broadband polarizers in a low loss planar waveguide platform is presented and characterized. Extinction greater than 78 dB is obtained with low loss for the desired polarization.

Applied Physics A, 2014

Planar waveguides with ultra-low propagation loss are necessary for integrating optoelectronic sy... more Planar waveguides with ultra-low propagation loss are necessary for integrating optoelectronic systems that require long optical time delay or narrowband optical filters. In this paper, we review an ultra-low loss planar waveguide platform that uses thin (\150 nm) Si 3 N 4 cores and thick ([8 lm) SiO 2 cladding layers. In particular, we discuss the performance of arrayed waveguide gratings (AWGs) fabricated with the platform. We propose the use of a practical design method that takes the statistical nature of worst-case crosstalk into account. We also demonstrate the measurement of amplitude and phase error distributions in an AWG using an optical backscatter reflectometer. We show that the waveguides have phase errors small enough to achieve AWG crosstalk below -30 dB, while crosstalk below -40 dB should also be possible with optimization of the component design.

22nd IEEE International Semiconductor Laser Conference, 2010

For the first time, a fully integrated hybrid silicon AWG based multiwavelength laser on SOI is p... more For the first time, a fully integrated hybrid silicon AWG based multiwavelength laser on SOI is presented. Four-channel operation with 360 GHz spacing and 25-35 dB SMSR is shown.

IEEE Photonics Conference 2012, 2012

ABSTRACT An optical 2R regenerator is presented. The device consists of an optical amplifier inte... more ABSTRACT An optical 2R regenerator is presented. The device consists of an optical amplifier integrated with a saturable absorber. Over 3 dB improvement in the extinction ratio is seen for 1 Gb/s signals at 1560 nm.

Silicon Photonics VI, 2011

ABSTRACT We present our work on fully integrated hybrid silicon optical buffers capable of holdin... more ABSTRACT We present our work on fully integrated hybrid silicon optical buffers capable of holding 40 byte packets at 40 Gb/s. These devices consist of low loss silicon waveguides and cascaded amplifiers to overcome passive losses in a 1.1 m long delay line. Since cascading multiple gain elements leads to ASE (noise) accumulation, reshaping elements in the form of saturable absorbers are integrated in the delay. Noise filtering in the buffer is investigated by simulating the eye diagram for a delay line with 1R regenerators and comparing it to that of a 2R regenerator. Finally, preliminary experimental data from the optical buffer is shown.

Smart Photonic and Optoelectronic Integrated Circuits XVI, 2014

ABSTRACT Free-space beam steering using optical phased arrays is a promising method for implement... more ABSTRACT Free-space beam steering using optical phased arrays is a promising method for implementing free-space communication links and Light Detection and Ranging (LIDAR) without the sensitivity to inertial forces and long latencies which characterize moving parts. Implementing this approach on a silicon-based photonic integrated circuit adds the additional advantage of working with highly developed CMOS processing techniques. In this work we discuss our progress in the development of a fully integrated 32 channel PIC with a widely tunable diode laser, a waveguide phased array, an array of fast phase modulators, an array of hybrid III-V/silicon amplifiers, surface gratings, and a graded index lens (GRIN) feeding an array of photodiodes for feedback control. The PIC has been designed to provide beam steering across a 15°x5° field of view with 0.6°x0.6° beam width and background peaks suppressed 15 dB relative to the main lobe within the field of view for arbitrarily chosen beam directions. Fabrication follows the hybrid silicon process developed at UCSB with modifications to incorporate silicon diodes and a GRIN lens.