PHTN1306: Lasers III
(2017 Fall)



Course Description

In this course, students will mathematically model DPSS laser systems and processes with an emphasis of application of models to real-world lasers. Beginning with a pass-by-pass model, several approaches will be taken to improve accuracy when applied to high-gain lasers including the treatment of laser amplifiers as multiple segments. The "gold standard" Rigrod model will be developed and introduced then adapted to handle real losses.

The effects of temperature on both diode and solid-state media will be investigated and application made to the design of DPSS systems (a convolution model being used to predict the effects of diode temperature drift on ultimate output power of the system). As well, thermalization of the LLL of quasi-three-level media will be investigated as re-absorption loss is considered (including such effects as Stark splitting of the LLL which occurs in most real solid-state media). Implications to laser design (e.g. end-pumping) will then be considered. Finally, other thermal effects such as phase-matching of SHGs will be examined and complete optimization of DPSS lasers will be considered.

Many models will use numerical methods and will utilize spreadsheets. The goal is application of theoretical models to real lasers and so a substantial lab component allows students can examine application of, and prove, various models developed in the course on a variety of lasers.

Prerequisites

It is required that you have obtained credit in PHTN1400 Principles of Laser Systems to enter this course. A mark of over 70% is highly recommended in the prerequisite course. Due to the mathematical rigor of this course, a strong understanding of mathematics is required for success in this course since both algebra and calculus are used extensively.

This course is offered as part of the Photonics Engineering Technology (3 year) Program at Niagara College.

Evaluation ...

Two midterm examinations, totalling 60%, as follows ...

Term test #1 on week 7 (2017/10/16) in class
A two-part test held in two consecutive lecture classes. Covers the Pass-by-pass model, the Rigrod approach (with application to real lasers), and diode parameter models.
Term test #2 on week 15 in class
A two-part test held in two consecutive lecture classes. Covers quasi-three-level lasers, Stark splitting of levels, the convolution model for predicting the effect of pump wavelength drift, and models for optimizing temperature.

Labs and assignments combined for a total of 40%

Course Policies ...

Course policies follow the Standardized Policies and Procedures for CEE (dated January 2011). In summary:

Complete course policies can be found in the Teaching and Learning Plan (T&LP) document found on Blackboard.

Textbook

Laser Modeling: A Numerical Approach with Algebra and Calculus by Csele, 2014, CRC Press, ISBN 9781466582507

The text, and the models presented within it, will be used extensively in this course including the Pass-by-pass model (chapter 3), Rigrod approach (chapter 4), Quasi-three-level lasers and Stark splitting (chapter 5), and Convolution model (chapter 5).


Course Notes and References

Laboratory Assignments

There are several labs and assignments in this course. Lab sessions are two-hours in length.

In line with departmental policies, the lab/assignment portion of this course MUST be passed SEPARATELY from the theory portion in order to pass this course. Late labs result in an immediate mark of ZERO with no exceptions and no excuses accepted (including the now infamous "my printer ran out of ink" and "my computer died"). Failure to submit a lab (and a late lab is considered failed and will receive a mark of zero) will result in the student being placed on course condition. Failure to submit a second lab results in immediate EXPULSION from the course.

Assignment 1: Pass-by-pass Model

Models from the text are applied to a high-gain laser.

Assignment due at the beginning of the lecture period (Tuesday 2017/09/19). Failure to submit this lab BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab or assignment results in immediate EXPULSION from the course without recourse).

Lab 1: Modeling a Fiber Laser

In this lab, key parameters of an Erbium-Doped Fiber Laser (EDFL) will be determined in the lab including the loss of system elements and saturation parameters of the amplifier. Determined parameters will then be applied to predict laser performance using several models including the Rigrod model. Included in the lab is a review of OSA usage, gain determination, and use of dBm and linear units.

Labs on week 3 and week 4 (Week starting 2017/09/18 and 2017/09/25) in V115


Lab Report due at the beginning of the lab period on the following week (beginning 2017/10/02) for each section - Tuesday labs are due at the beginning of class on Tuesday, etc. Failure to submit this lab BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab results in immediate EXPULSION from the course without recourse).

There are no labs on week 6 starting Monday 2017/10/09 due to the Thanksgiving holiday

Lab 2: Laser Diode Characteristics

In this lab, you will measure parameters of a typical laser diode including the L/I curves, threshold current as a function of temperature (where threshold is measured by the two-line method), output spectrum, and wavelength temperature coefficient.

Labs on week 7 (Week starting 2017/10/16) in V115


Lab Report due at the beginning of the lecture period (Tuesday 2017/10/31 immediately after the break). Failure to submit this assignment BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab or assignment results in immediate EXPULSION from the course without recourse).

There are no labs on week 8 starting Monday 2017/10/23 due to the Study Break

Lab 3: Re-Absorption Loss in a DPSS System

Re-absorption loss of the 946nm quasi-three-level transitions in Nd:YAG will be accurately computed and applied to predictions of output pump power for a commercial laser based on the temperature of the amplifier. Specific attention will be paid to Stark levels, and saturation effects of the LLL thermal population will be examined.

Lab on week 10 (Week Starting 2017/11/06) in V115
PRELAB (worth 25%) due on entry to the lab period

Lab Report due at the beginning of the lab period on the following week (2017/11/13). Failure to submit this lab BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab results in immediate EXPULSION from the course without recourse).

Lab 4: Predicting Pump Absorption using the Convolution Technique

Gain of the amplifier, which is a function of the actual absorption of pump radiation, is calculated using the convolution technique which begins with knowing the pump spectrum and the wavelength coefficient of temperature. This will allow the determination of the effect of temperature drift on the output of a DPSS laser.

Lab on week 11 (Week Starting 2017/11/13) in V115
PRELAB (worth 25%) due on entry to the lab period

Lab Report due at the beginning of the lab period on the following week (2017/11/20). Failure to submit this lab BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab results in immediate EXPULSION from the course without recourse).

Lab 5: Measuring Pump Absorption

Continuing from the previous lab, then actual gain of the amplifier is measured as a function of pump diode temperature (and hence wavelength).

Lab on week 12 (Week Starting 2017/11/20) in V115
PRELAB (worth 25%) due on entry to the lab period

Lab Report due at the beginning of the lab period on the following week (2017/11/27). Failure to submit this lab BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab results in immediate EXPULSION from the course without recourse).

Lab 6: SHG and Phase Matching

The effects of temperature on phase-matching and hence SHG efficiency are examined on a 473nm DPSS laser.

Lab on week 13 (Week Starting 2017/11/27) in V115
PRELAB (worth 25%) due on entry to the lab period

Lab Report due at the beginning of the lab period on the following week (2017/12/04). Failure to submit this lab BEFORE or ON the due date and time will result in an immediate ZERO on the lab and placing of the student on course condition (meaning one more late or missing lab results in immediate EXPULSION from the course without recourse).

Contacts:

For the Photonics Technician/Technology programs ...
Program Coordinator Alexander McGlashan
Office: S106
Telephone (905) 735-2211 x.7513
E-Mail:

For this specific course ...
Professor Mark Csele
Office: V113E (Office hours are POSTED on the Electroluminescent panel on the office door)
Telephone: (905) 735-2211 x.7629
E-Mail: (Be sure to include 'Lasers' in the subject line to avoid deletion by an anti-spam filter)

URL: http://technology.niagarac.on.ca/staff/mcsele

You are visitor # since Sept, 2017
Copyright (C) Professor M. Csele and Niagara College, Canada, 2017
This course is part of the TECHNOLOGY division

Some images and text excerpted from Laser Modeling: A Numerical Approach with Algebra and Calculus by Csele, CRC Press, 2014, ISBN 9781466582507. Further reproduction in any form is prohibited without written approval from the publisher.