Dr. Almantas Pivrikas
Bachelor, Master's, PhD

Senior lecturer

About me

PhD scholarships available now! Email me please for more details

Short CV

Dr. Almantas Pivrikas has graduated Bachelor’s degree in 2000 at the Faculty of Physics and Master’s degree in 2002 at the Solid State Electronics and Condensed Matter Physics Department at Vilnius University, Lithuania with Prof. Gytis Juska.
Almantas completed his PhD studies in 2006 in Physics at Abo Akademi University, Finland with Prof. Ronald Osterbacka.
He was a postdoctoral fellow (2007-2010) at the Physical Chemistry Department, Linz Institute for Organic Solar Cells (LIOS), Johannes Kepler University Linz, Austria with Prof. Niyazi Serdar Sariciftci.
Almantas received DECRA fellowship (2011-2014) at the University of Queensland, Brisbane, Australia, with Prof. Paul Burn and Prof. Paul Meredith.
Since 2015 he has been a senior lecturer at Murdoch University, Perth, Australia.

 

Research interests

The aim of my research is to develop the next-generation modern opto-electronic devices.

Expertise area. If I’d have to say it in one sentence, I’d say like this: There is nothing I don’t know about semiconductors and electronic devices. Challenge me, or use my knowledge to make something new and great!

- Opto-electronic device fabrication and characterisation
- Electrical conductivity and photoconductivity studies
- Charge transport, charge mobility and recombination
- Spectroscopy, optical interference, light absorption, photoluminescence
- Development of novel techniques for device and material characterization

 

Research outputs
My h-index, list of publications and citations can be found at his public Google Scholar profile:
http://scholar.google.com/citations?user=rVsRFLoAAAAJ

 

Contact details
Murdoch University
School of Engineering and Information Technology
Science and Computing building Nr.245
Room Nr. 2.017
90 South Street
Murdoch 6150
Perth, Western Australia
Mobile phone: +61 466 965 314
email: a.pivrikas@murdoch.edu.au
Skype ID: “pivrikas”
My room/office (SC2.017) is located EXACTLY here: https://goo.gl/maps/j4ujD52WQe92
(car parking is free of charge after 4PM and since I work long hours I prefer evening meetings)

 

 

My affiliation, for use in publications
School of Engineering and Information Technology, Murdoch University, Perth 6150, Australia.

 

Some fun stuff can be found at Almantas Pivrikas blog.

 

INFORMATION FOR STUDENTS

Step-by-step guide to research degrees
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Future-research-students/

Scholarships for domestic students
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Future-research-students/Admission-and-scholarships/Domestic-students-scholarships/
Apply for admission – domestic students
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Future-research-students/Admission-and-scholarships/Domestic-student-applications/

Scholarships for international students
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Future-research-students/Admission-and-scholarships/International-student-scholarships/
Application for admission – International students
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Future-research-students/Admission-and-scholarships/International-student-applications/

Also, please read the following info
Graduate Research Degrees Policies, Guidelines & Regulations
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Policies-guidelines-and-regulations/
Confirmation of Candidature – your first major milestone top be reached after 6 month
http://our.murdoch.edu.au/Research-and-Innovation/Resources-for-students/Confirmation-of-Candidature/

Teaching area

Energy Science and Physics courses

Research areas

Opto-electronic devices we study are:

- Photovoltaic solar cells
- Photodetectors and photosensors
- Field effect and electrochemical transistors
- Light emitting diodes
- Chemical and bio-sensors
- Electrochemical systems, batteries, neurons, cells etc.

Typical materials we use in modern opto-electronic devices are:
- Solid state semiconductors: organic molecules, polymers, carbon structures, silicon, germanium, gallium nitride, selenium, perovskites etc.
- Electrolyte based systems: batteries, organic-inorganic interfaces
- Modern nano-structured materials eg. quantum dots and structures, nano-needles etc.
- Bio-systems: neuron and cell signalling etc.

 

What services can we offer for academic and industry collaborations?

Electric measurements:

- Electrical conductivity and photoconductivity
- Electron density during injection
- Space Charge Limited Injection (SCLC), Ohmic injection, contact limited or trap limited injection
- Drift velocity of charge in electric field
- Charge diffusion coefficients due to concentration gradient
- Mobility of electrons and holes or positive and negative ions
- Charge trap states: trap densities, charge capture and release times
- Lifetime and bimolecular recombination coefficient of photogenerated charge carriers
- Frequency dependent dielectric constant (relative permittivity).

Optical measurements:

- Light absorption, transmission or reflection spectra in UV, VIS, IR
- Optical constants: refractive index n and extinction (attenuation) coefficient k
- Thin film optical interference spectra
- Second (or higher) harmonic generation
- Amplified spontaneous emission, lasing
- Photoluminescence spectra and time decay for exciton lifetimes.

Numeric modelling, simulations and theory:

- In general our custom developed drift-diffusion model does provide predictions for any metal-semiconductor-metal, metal-semiconductor-insulator structures, diode (bulk) and field effect transistor (planar) geometries.
- Charge transport: drift, diffusion, and space charge effects
- Charge trapping and dispersive transport
- Hot photocarrier transport
- Charge hopping and localized transport mechanisms in disordered systems
- Recombination mechanisms of photogenerated electrons and holes
- Computational screening of possible device parameters in device optimization or material selection

We also develop novel techniques for reliable experimental measurements when classical methods fail.

 

List of equipment in our spectroscopy laboratory

Manuals for all equipment listed below I can provide on request.

- Laser, nanosecond pulse duration. QLI Model Q1B-10. Wavelengths 355nm, 532nm and 1064nm. High pulse intensity, 10 mJ.
- Oscilloscope. Tektronix model DPO7104C.
- Arbitrary function generator. Tektronix AFG3102C 100 Mhz, 2 channels. Special feature – superimpose any external signal with an internal one synthesized by the generator.
- Current-Voltage sources and measurement units. Keithley model 2450.
- Lock-in amplifier. Stanford SR830.
- Solar simulator. Model Spire SPI-Sun Simulator 5600SLP.
- Various optical and opto-mechanical components such as Neutral density filters, bandpass filters, laser mirrors, optical mounts, translation stages etc.

Current projects

PhD scholarships in electronics, charge transport and electrical signalling are presently available. Please don’t hesitate to contact me anytime to find out more details about available PhD positions, topics and requirements for an application.

Publications

Journals

  • Pivrikas, A., Marks, M., Kumar, P., Kroon, R., Barr, M., Nicolaidis, N., Feron, K., Fahy, A., Mendaza, A., Kilcoyne, A., Müller, C., Zhou, X., Andersson, M., Dastoor, P., Belcher, W., (2016), Nano-pathways: Bridging the divide between water-processable nanoparticulate and bulk heterojunction organic photovoltaics, Nano Energy, 19, , pages 495 - 510.
  • Philippa, B., White, R., Pivrikas, A., (2016), A route to high gain photodetectors through suppressed recombination in disordered films, Applied Physics Letters, 109, 15, pages -.
  • Pivrikas, A., Philippa, B., White, R., Juska, G., (2016), Photocarrier lifetime and recombination losses in photovoltaic systems, Nature Photonics, 10, 5, pages 282 - 283.
  • Pivrikas, A., Philippa, B., Shoaee, S., Jiang, W., White, R., Burn, P., Meredith, P., (2015), Charge Transport without Recombination in Organic Solar Cells and Photodiodes, The Journal of Physical Chemistry Part C: Nanomaterials, Interfaces and Hard Matter, 119, , pages 26866 - 26874.
  • Pivrikas, A., (2015), Photocarrier drift distance in organic solar cells and photodetectors, Scientific Reports, 5, 9949, pages -.
  • Pivrikas, A., (2014), Dynamics of Charge Generation and Transport in Polymer-Fullerene Blends Elucidated Using a PhotoFET Architecture, ACS Photonics, 1, 2, pages 114 - 120.
  • Pivrikas, A., Kadashchuk, A., Sitter, H., Genoe, J., Bassler, H., (2012), Electric field dependence of charge carrier hopping transport within the random energy landscape in an organic field effect transistor, Physical Review B- Condensed matter and materials physics, 86, 4, pages -.

Full updated list of my publications with citations can be found at Google Scholar:
http://scholar.google.com.au/citations?user=rVsRFLoAAAAJ&hl=en

Ten career-best publications

1. A Review of Charge Transport and Recombination in Polymer/Fullerene Organic Solar Cells.
A. Pivrikas, G. Juska, R. Österbacka, and N.S. Sariciftci (I am a corresponding author).
Progress in Photovoltaics: Research and Applications 15, 677 (2007). Impact Factor 7.712.
This paper summarizes out achievements in charge transport and recombination in organic solar cells.

2. Measuring internal quantum efficiency to demonstrate hot exciton dissociation.
A Armin, Y Zhang, PL Burn, P Meredith, A. Pivrikas (I am a corresponding author).
Nature Materials 12 (7), 593-593 (2013). Impact Factor 35.7. Funded by DE120102271.
In contrast to a widespread believe (results published at high impact journals), this work shows that the excess energy of excitons is not utilized to increase efficiency organic solar cells because the dissociation itself already very efficient.

3. Bimolecular recombination coefficient as a sensitive testing parameter for low-mobility solar-cell materials.
A. Pivrikas, G. Juska, A.J. Mozer, M. Scharber, K. Arlauskas, N.S. Sariciftci, H. Stubb, and R. Österbacka.
Physical Review Letters 94, 176806 (2005). Impact Factor 7.943.
For the first time we have observed an unexpected non-Langevin bimolecular recombination in organic materials. This discovery led to numerous clarifications of photophysics and performance of organic solar cells.

4. Charge carrier mobility in regioregular poly(3-hexylthiophene) probed by transient conductivity techniques: A comparative study.
A. Mozer, N.S. Sariciftci, A. Pivrikas, R. Österbacka, G. Juska, and H. Bassler.
Physical Review B 71, 035214 (2005). Impact Factor 3.767.
This paper demonstrates the novel charge transport characterisation technique in organic semiconductors, quantifies the specific parameters and highlights the borders of technique applicability.

5. Time-dependent mobility and recombination of the photoinduced charge carriers in conjugated polymer/fullerene bulk heterojunction solar cells.
A. J. Mozer, G. Dennler, N.S.  Sariciftci, M. Westerling, A. Pivrikas, R. Österbacka, and G. Juska.
Physical Review B 72, 035217 (2005). Impact Factor 3.767.
For the first time we have reported a novel result quantifying the time-dependent charge transport in strongly disordered organic solar cells. This led to further progress in the field..

6. Charge carrier mobility and lifetime versus composition of conjugated polymer/fullerene bulk-heterojunction solar cells.
G. Dennler, A. J. Mozer, G. Juska, A. Pivrikas, R. Österbacka, D. A. Fuchsbauer, and N. S. Sariciftci.
Organic Electronics 7, 229 (2006). Impact Factor 4.021.
Previously overlooked relation between charge carrier mobility and lifetime product is reported. It highlights the importance of both in organic solar cells.

7. Substituting the postproduction treatment for bulk-heterojunction solar cells using chemical additives.
A. Pivrikas, P. Stadler, H. Neugebauer, and N.S. Sariciftci (I am a corresponding author).
Organic Electronics 9, 775 (2008). Impact Factor 4.021.
Novel technique is reported allowing to control the nanoscale morphology and improve the efficiency of organic solar cells. The reason behind the improvement are quantified.

8. Mobility and density relaxation of photogenerated charge carriers in organic materials.
R. Österbacka, A. Pivrikas, G. Juska, K. GeneviCius, K. Arlauskas, and H. Stubb.
Current Applied Physics 4, 534 (2004). Impact Factor 1.782.
For the first time we have reported a novel result quantifying the time-dependent charge transport in strongly disordered organic materials. Experimental results well matched with theoretical predictions demonstrating the validity of the theory.

9. Langevin recombination and space charge perturbed current transients in pi-conjugated polymers.
A. Pivrikas, G. Juska, R. Österbacka, M. Westerling, M. ViliS«nas, K. Arlauskas, and H. Stubb.
Physical Review B 71, 125205 (2005). Impact Factor 3.767.
Space charge limited current transient for the first time observed in organic semiconductors. Paper highlights the specifics of classical theory to measure carrier mobility in organic materials.

10. The impact of hot charge carrier mobility on photocurrent losses in polymer-based solar cells
B. Philippa, M. Stolterfoht, P. L. Burn, G. Juška, P. Meredith, R. D. White and A. Pivrikas (I am a corresponding author).
Nature Scientific Reports 4, 1 (2014). Impact Factor 5.078. Funded by DE120102271.
Groundbreaking results demonstrating the nature of charge transport and fallacy of photocarrier lifetime measurements in organic solar cells and disordered materials in general.