Title of article :
Two-dimensional ferroelectricity in monolayer PVDF Langmuir–Blodgett films studied by optical second-harmonic generation
Author/Authors :
Fokin، نويسنده , , Yu.G. and Misuryaev، نويسنده , , T.V and Murzina، نويسنده , , T.V and Palto، نويسنده , , S.P. and Petukhova، نويسنده , , N.N. and Yudin، نويسنده , , S.G. and Aktsipetrov، نويسنده , , O.A.، نويسنده ,
Issue Information :
هفته نامه با شماره پیاپی سال 2002
Abstract :
The two-dimensional (2D) ferroelectricity in monolayer Langmuir–Blodgett (LB) films of copolymer vinylidene fluoride with trifluoroethylene (PVDF/TrFE) is studied by optical second-harmonic generation (SHG). The SHG temperature dependences are studied in order to reveal the ferroelectric behaviour of the films. For the monolayer LB films of PVDF/TrFE, as well as for the multiplayer LB films, a wide hysteresis in the SHG intensity under heating and consequent cooling is observed. This hysteresis is attributed to the first-order ferroelectric–paraelectric phase transition in the extreme case of literally 2D ferroelectric films. It is demonstrated that the main contribution to the nonlinear response of the LB films of PVDF/TrFE originates from fluctuations of the nonlinear polarization in inhomogeneous film structure.
Keywords :
Surface electronic phenomena (work function , Surface potential , etc.) , second harmonic generation , Surface thermodynamics (including phase transitions) , Surface states , Non-linear optical methods
Journal title :
Surface Science
Journal title :
Surface Science
