As ones know

the polaron is a quasiparticle formed by an electron and phonons.Due to Coulomb interaction

the electron will make the lattice deformation take place

meanwhile

the deformation potential induced by the lattice deformation will exert on the electron

the electron-phonon interaction influence doubtless on the state of motion of an electron

for example

the energy band and effective mass of an electron could change by the interaction

the electron can also be trapped by the deformable lattice

therefore

the research on the polaron is very important in understanding optical and transport properties of a solid. Studying electron-phonon interaction has been a main subject in condensed matter physics;in experiments

the influences of the temperature on the forbidden-band width of semiconductors have been observed very early

with the increase of the temperature

the forbidden-band width of most semiconductors will narrow

but a few will widen

these situations are closely relevant to the electron-phonon interaction.In particular

recently

a large amount of experimental results

ranging from infrared spectroscopy to transport properties involving the colossal magnetoresistance and high-

T

c

superconductivity

has pointed out the importance of the electron-phonon interaction

which has renewed the interest in studying the models of the electron-phonon coupled system

especially

the Holstein polaron

for its relative simplicity

is the most considered model for the interaction of a single tight-binding electron coupled to phonons. In the past several decades

the Holstein poloron has been studied in detail in one-dimensional lattices

various theoretical methods

such as variational approaches

the Global-Local variational method

the coherent -state expansion method

have been developed to study features of the Holstein polaron including ground-state energy

polaron energy band

effective mass and so on.However

so far

the work considering the influences of the temperature on features of the Holstein polaron is little still. The main aim of this paper is to investigate the influences of the temperature on the energy-band width and the effective mass of the Holstein polaron by using the canonical transformation method.It is shown that

at certain coupling strength

the energy-band width of the Holstein polaron will narrow and the effective mass will augment with the increase of the temperature

in particular

when electron-phonon coupling strength is big enough

the energy-band width will become zero rapidly in small region of temperature

in fact

the situation is rapid transition of the polaron from the energy-band state to the self-trapping local state

this is an interesting result obtained in the paper.It is obvious that these features of the Holstein polaron are very useful in explaining optical and transport properties of a solid.