Wavelength Converters Wavelength Converters Presented by Eduardo - PowerPoint PPT Presentation

Wavelength Converters Wavelength Converters � Presented by Eduardo Presented by Eduardo � Gonzalez, Electrical Gonzalez, Electrical Engineering, Sr. Engineering, Sr. � Mentor: Joe Summers Mentor: Joe Summers � � Faculty Adviser: Daniel J. Faculty Adviser: Daniel J. � Blumenthal, Ph.D Ph.D Blumenthal, � Funding: D.A.R.P.A. Funding: D.A.R.P.A. �

The Big Picture The Big Picture � A A Wavelength Wavelength � Converter is a device is a device Converter that converts data from that converts data from one incoming wavelength one incoming wavelength to another outgoing to another outgoing wavelength. wavelength. � They are used in Fiber They are used in Fiber � Optic Communication Optic Communication Systems. Systems. � WDM (Wavelength WDM (Wavelength � Division Multiplexing) Division Multiplexing) Networks: Transmit data Networks: Transmit data simultaneously at multiple simultaneously at multiple carrier wavelengths (or carrier wavelengths (or equivalently frequency). equivalently frequency).

Research Goals and Objectives Research Goals and Objectives � Monolithically integrate widely tunable Monolithically integrate widely tunable � laser and a wavelength converter. laser and a wavelength converter. � Demonstrate that any input wavelength Demonstrate that any input wavelength � can be converted to any output can be converted to any output wavelength. wavelength. � Design Multimode Interference (MMI) Design Multimode Interference (MMI) � Devices (Optical Splitter). Devices (Optical Splitter). � Test devices for optimization. Test devices for optimization. �

BeamProp Simulation and Data BeamProp Simulation and Data � This software This software � monitors light monitors light through a chosen through a chosen pathway. pathway. � Vary width and Vary width and � length to minimize length to minimize device area. device area. � Look for 50% Look for 50% � output on each arm. output on each arm. � Waveguide end Waveguide end � tapered to eliminate tapered to eliminate coupling. coupling.

Interferometer - - cross cross Interferometer phase modulation phase modulation Cross-Phase Modulation Principle π phase shift Data in No CW light out Converted CW in Signal Out • Semiconductor optical amplifiers used to achieve π phase shift • Incoming data disturbs phase balance ⇒ data conversion

Laser Tuning and Reflection Spectrum Laser Tuning and Reflection Spectrum – Changing the current in each Changing the current in each – mirror changes it’s index. mirror changes it’s index. – We make use of the reflection We make use of the reflection – spectra to observe the spectra to observe the periodic mirror maxima. periodic mirror maxima. 2 1 3 – Inducing small index changes – Inducing small index changes in one mirror relative to the in one mirror relative to the Power other causes adjacent other causes adjacent reflectivity maxima to come reflectivity maxima to come Front Mirror Gain Phase Rear Mirror into alignment. into alignment. Front Mirror Gain Phase Rear Mirror – Lasing occurs at the pair of Lasing occurs at the pair of – B ack Reflectanse maxima that are aligned. maxima that are aligned. Front Wavelength

Laser Tuning Laser Tuning I:Front I:Back Wave- - I:Front I:Back Wave Mirror Mirror length Mirror Mirror length (mA mA) ) (mA mA) ) (nm) ( ( (nm) 24 20 1528 24 20 1528 21 20.2 1533 21 20.2 1533 4 0 1542 4 0 1542 24 3.7 1552 24 3.7 1552 0 0 1559 0 0 1559 3 20 1566 3 20 1566

Future Plans Future Plans � Test devices to observe successful Test devices to observe successful � wavelength conversion. wavelength conversion. � Observe errors in data transmission using Observe errors in data transmission using � the BER detector. the BER detector. � Test the devices at 40 Test the devices at 40 Gbps Gbps (Gigabits per (Gigabits per � second) second)

Acknoledgements Acknoledgements � Joe Summers, Daniel J. Blumenthal, Joe Summers, Daniel J. Blumenthal, Ph.D Ph.D, , � and Milan Masanovic Masanovic, Ph.D. , Ph.D. and Milan � INSET Group: Trevor INSET Group: Trevor Hirst Hirst, Nick Arnold, , Nick Arnold, � Nick Northern, Liu- -Yen Kramer, and Yen Kramer, and Nick Northern, Liu Evelyn Hu Hu. . Evelyn