Polarization ntawm dielectrics

A phenomenon nyob rau hauv uas tshwm sim nyob rau hauv lub insulator yog tsuas yog siv nyob rau hauv tus nqi ntawm cov xaav hais txog nqi, los yog muaj ib tug tig fais dipoles, tau txais lub title nyob rau hauv physics polarization ntawm dielectrics. Thaum lub sij hawm tus txheej txheem no tej zaum yuav tshwm sim yog nthawv, vim internal ua, los yog nyob rau hauv tus ntawm lwm rog, ua ntej ntawm tag nrho cov, cov hluav taws xob teb.

Lub physico-zauv thiaj yog tsiag ntawv los ntawm polarization vector sawv cev rau ib dipole lub sij hawm ntawd, uas yog pom nyob rau hauv kev sib raug zoo mus rau lub magnitude ntawm lub dielectric volume. Heev feem ntau nyob rau hauv lub cev cov ntsiab lus teb ntawm kev siv yooj yim zog cov ntsiab lus - polarization. Qhov no parameter yog siv tsis tau tsuas yog mus raws li lub macroscopic lub xeev. Nws yuav siv tau los piav qhia txog tej phenomena muaj zog uas characterize lub polarization ntawm dielectrics.

Nyob rau lub hauv paus ntawm nqe lus no, peb yuav npaj ib qho tsos mob ntawm tus phenomenon. Xws li ib tug lub xeev ntawm cov dielectric nyob rau hauv uas nws yog kuaj cov xub ntiag ntawm lub dipole lub sij hawm ntawd nyob rau txhua kis ntawm nws volume, thiab characterizes lub polarization ntawm dielectrics.

Qhov no tshwm sim yog tsis meej xwm nyob rau hauv cov xwm. Paub qhov txawv xws hom raws li lub ntxias polarization ntawm dielectrics, uas yog tshwm sim los ntawm tus ntawm lwm fais teb, tshwm sim, tsim nyob rau hauv lub qhaj ntawv ntawm sab nraud cov neeg ua hauj polarization mechanical (ferroelectric) yog tsim los ntawm qhov kev txiav txim ntawm cov neeg kho tshuab cov neeg ua hauj, Thaum tshav kub kub uas tshwm sim vim kub hloov mus hloov los.

Lub peculiarity ntawm polarization raws li ib tug lub cev tshwm sim yog hais tias nws muaj zoo tsis ntxim rau cov nqi ntawm tag nrho cov nqi ntawm ib tug homogeneous dielectric, txawm taw tes rau ntawm nws volume yog tsis xaiv. Nyob rau tib lub sij hawm, polarization tshwm sim nyob rau hauv lub tsim ntawm bound nqi rau cov dielectric nto. Cov nqi lub hauv paus ntawm lub teb nrog ib co ntxiv nro, uas yog qhia tiv thaiv cov vector ntawm lwm vector teb.

Tseem ceeb nyob rau hauv qhov teeb meem sawv, thiab polarization ntawm dielectrics kev faib raws li nws tus kheej mechanisms. Nyob rau hauv no hwm nws muaj xws li xws hom:

- Migration yog cov yam ntxwv ntawm cov ntaub ntawv nyob rau hauv uas cov qauv yog kom meej meej pom khaubncaws sab nraud povtseg nrog txawv conductivity. Tej polarization yog yus muaj los ntawm ib tug ncua txiav txim;

- hluav taws xob polarization yog kom tshem tau cov neeg zoo li ntawm atoms nyob rau hauv tus ntawm lwm hluav taws xob teb. Qhov no - tus ceev tshaj hom polarization;

- ion yog tsiag ntawv los ntawm tib yam li cov electronics, tab sis nyob rau hauv cov ntaub ntawv no muaj yog tsis muaj xaav zoo li ntawm atoms, thiab tsiv ntawm cov qauv siv lead ua ntxaij ntoo tshuaj;

- dipole, los yog raws li nws yog hu ua orientation polarization yog yus muaj los ntawm loj losses, qhov ua rau ntawm uas yog tus yawm cov nuj nqis ntawm lub zog kom kov yeej lub internal sib txuas nyob rau hauv lub dielectric. Rau lub orientation ntawm lub polarization ntawm dielectric yam ntxwv tshwm sim ntawm zoo-txhais orientation ntawm dipoles;

- electron so yog yus muaj los ntawm muaj ib tug kev orientation defect ntawm electrons;

- ion-so polarization dielectrics qhia nyob rau hauv mus ions uas muaj muaj zog nrog kev sib txuas thiab tsau stably nyob rau hauv lub siv lead ua ntxaij ntoo ntshav khoom qauv;

- ib ntu no kuj muaj nyob rau hauv particular orientation dielectric hais, tab sis nyob rau hauv cov ntaub ntawv no cov ntsiab yog cov ntau yam impurities, uas muaj ib tug dielectric substance. Qhov no polarization tshwm sim ntau maj mam;

- txawj (txawj) cai nyob rau hauv dielectrics nrog ib tug heev permeability tsis, lawv hu ua ferroelectrics;

- yus coincidence dielectric resonance zaus ntawm lub electrons ntawm frequencies kuj thereon teb, li no, nruj me ntsis hais lus, xws li ib tug lub npe.

Raws li ib tug txoj cai, nyob rau hauv txhua tus neeg mob, tshwj tsis yog rau lub resonant polarization, nws cov nuj nqis nce mus txog ib tug tshaj plaws nyob rau hauv zoo li qub teb.