Spin Dimers for Quantum Magnets What is Quantum

«Spin Dimers for Quantum Magnets»

What is Quantum Computers? A quantum computer is a device based on quantum magnets for computation that makes direct use of quantum mechanical phenomena, such as superposition and entanglement, to perform operations on data. Richard Feynman 1982 A quantum computer maintains a sequence of qubits But what can we used as qubits? 1

Spin Dimers B 2

Working Horses Why Nitroxides? - stability. - easy to synthesize. - structure-properties variation. Energy Limitation Jintra/kb≈ 10 K 3

Quantum Calculations 5

DFT B 3 LYP 6 -31 G* BLYP Broken Symmetry - 18. 7 K - 2. 5 K -14. 4 K - 2. 7 K -16. 8 K -10. 1 K 6

Biphenyl Synthesis Jintra= -14 K 7

Terphenyl and Bis(pyrasolyl) Synthesis Jintra= -1. 7 K Jintra= -32 K 8

Tolane and Diacetylene Models Jintra= -9. 6 K Jintra= -4. 8 K Т = 0. 191 K Jinter= -1…-2 K 9

Heteroatom Insertion Jintra= -10. 7 K 10

Summary - 14 K - 1. 7 K - 32 K -9. 6 K -4. 8 K -10. 7 K 11

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Оборудование Superconducting Quantum Interference Device (SQUID) χ ac ac-susceptibility data were recorded using an ultra-high resolution ac-susceptometer adapted to a 3 He-4 He top-loading dilution refrigerator. The compensated-coil susceptometer is optimized for measuring small single crystals in the mg range. The system is equipped with a 12 T superconducting magnet. Nonius Kappa CCD (Mo kα, μ = 0. 71073 Å) diffractometer equipped with a graphite monochromator. 19

Acknowledgments International Max Planck Research School for Polymer Materials Professor Dr. Baumgarten Martin project leader, conjugated polymers group Max Planck Institute for Dr. Volker Enkelmann Polymer Research Max Planck Institute für Polymerforschung Professor Dr. Michael Lang Department of the Physical Institute Johann Wolfgang Goethe-Universität Frankfurt am Main Dr. Yulia Borozdina Max Planck Institute für Polymerforschung 20