Gredig Research Lab: Gas Sensors, Solar Cells, Low ... · Outline n Career of a Physicist n Research at CSULB ¨Gas Sensors ¨Solar Cells ¨Magnetism n Applications (Energy-Related)

Gredig Research Lab:Gas Sensors, Solar Cells,

Low-Dimensional Magnetism

Thomas GredigDepartment of Physics & AstronomyCalifornia State University, Long Beach

Bite of Science, February 22, 2016

Outline

n Career of a Physicistn Research at CSULB

¨Gas Sensors¨Solar Cells¨Magnetism

n Applications (Energy-Related)¨Energy Absorption (Cans)¨Energy Conversion (Solar Cells)¨Energy Storage (Aluminum Foil)

n Outreach: PhysTEC, Society of Physics Students

Typical Career Road Map

Professor

Post-doc

Ph.D.

B.S.

A Quarter Century

n B.S. Physics (~ 4 years)n M.S. Physics (~ 2 years)n Ph.D. Physics (~ 3 years)n Post-doctoral positions (3 – 5 years)n Assistant Professor (5 – 6 years)n Associate Professor (4 – 5 years)n Professor

CSU Long Beach – Gredig Group

Open Questions

n Gas Sensors¨Monitor gas leakage¨Measure emissions in industry¨Detect explosives, biological warfare agents

n How to distinguish different molecules?n What materials are suitable?

Organic Material: Phthalocyanine

H

C

N

FePhthalocyanine MoleculeImage: T. Gredig

me.

me.met

hano

l

met

hano

l

me.

200 400 600

0.8

1.0 n

orm

aliz

ed c

urre

nt

Time (min)

small grains (25 C) large grains (200 C)

Transport Measurement in CoPc

• sensitivity to analyte (reversible)• more drift for higher growth temperature

dosage

Optimized Sensor

n Patent: U.S. 8,384,409:¨Ultra-thin Organic TFT Chemical Sensor

n Applied Physics Letters, 90, 263506 (2007).

Zinc Phthalocyanine – based Solar Cell

17

Open Questions: What material? What structure (smooth, rough)?

M.S. Thesis of Eric Muckley, now at Oak Ridge Laboratories

Finished Solar Cell

18 Image: Eric Muckley, CSU Long Beach

Challenges in Magnetism Today (Applications)

n Stronger magnets (work = force * distance)n Lighter magnets (mass)n Transparent magnetsn Optically active magnetsn Flexible (non-brittle) magnets

Strongest Magnets

Neodymium Iron Boron Magnets

http://www.magnetnrg.com/pm-history.html

Thermal Gradient Purification

Vacuum Deposition System

Thermal Evaporation (Sublimation)

Typical Samples: 10 x 4 mm2

Magnetic Relaxation in 1D

Gredig et al., Phys. Rev. B (2017).

General Approach to Research

n Preparation: Sample / System

n Model / Simulation

n Experiment

n Comparison with Prediction

n Use Model, refine, new Predictions

General Approach to Research

n Preparation: Sample / System¨Build a Capacitor (Al foil, …)

n Model / Simulation¨PhET simulations (phet.colorado.edu)

n Experiment ¨Arduino microcontroller

n Comparison with Prediction¨R, GnuPlot, Python

n Use Model, refine, new Predictions

Heating and Cooling of Black/Silver Can

Black

Silver

Applications: Energy Conversion

n Solar Cells: ~ $5n What is the dependence on angle?n What is the shape of the I-V curve?n How does light color, temperature, area, light

intensity affect the solar cell performance?

PhET Simulation: Circuit Construction Kit

n Phet.Colorado.edu

Need Ideas?

n American Association of Physics Teachers¨K-12 Teacher Portal

n American Journal of Physics¨Read¨Publish

n AAPT ComPADRE¨Resource Library

Outreach

n High School Teacher in Residencen PHYS 390 - Exploring Physics Teaching

¨Visits to H.S.n PhysTEC at CSULB

¨HS teachers share experiments on Thursdays on Demo Day

¨Newsletter¨ https://web.csulb.edu/colleges/cnsm/sas/phystec/¨Questions, email: [email protected] or

call (562) 985-7026

PhysTEC

Society of Physics Students (SPS)n CSU Long Beach SPS visited High Schools with Physics Demos