Photo-induced optical activity in phase-change memory materials.
We demonstrate that optical activity in amorphous isotropic thin films of pure Ge2Sb2Te5 and N-doped Ge2Sb2Te5N phase-change memory materials can be induced using rapid photo crystallisation with circularly polarised laser light. The new anisotropic phase transition has been confirmed by circular dichroism measurements. This opens up the possibility of controlled induction of optical activity at the nanosecond time scale for exploitation in a new generation of high-density optical memory, fast chiroptical switches and chiral metamaterials.
1] Department of Materials, University of Oxford, Parks Road, Oxford. OX1 3PH, United Kingdom [2] Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0FA, UK.
Konstantin B
KB
Borisenko
1] Department of Materials, University of Oxford, Parks Road, Oxford. OX1 3PH, United Kingdom [2] Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0FA, UK.
Janaki
J
Shanmugam
Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford. OX1 3PU, United Kingdom.
Benjamin A O
BA
Williams
Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford. OX1 3PU, United Kingdom.
Paul
P
Ewart
Optoelectronics Research Centre, University of Southampton, Southampton. SO17 1BJ, United Kingdom.
Behrad
B
Gholipour
Optoelectronics Research Centre, University of Southampton, Southampton. SO17 1BJ, United Kingdom.
Daniel W
DW
Hewak
Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom.
Rohanah
R
Hussain
Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom.
Tamás
T
Jávorfi
Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom.
Giuliano
G
Siligardi
1] Department of Materials, University of Oxford, Parks Road, Oxford. OX1 3PH, United Kingdom [2] Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0FA, UK.
Angus I
AI
Kirkland