CAJ | 학술논문

采用传统的高温固相烧结法制备了多晶样品（La1－x Gdx ）4／3 Sr5／3 Mn2 O7（x ＝0，0．05），利用 XRD 检测了两样品的结构，结果表明：两样品均为 Sr3 Ti2 O7型四方结构，空间群为 I4／mmm，通过物性测量系统（PPMS）和超导量子磁强计（SQUID）测量了样品的磁性（M－T）以及电性（ρ－T），结果发现：两样品在低温区存在长程的铁磁态；当 Gd 掺入后，由于引起了结构的畸变，削弱了双交换作用，致使样品（La1－x Gdx ）4／3 Sr5／3 Mn2 O7（x ＝0．05）的三维（3D）磁有序转变温度 T3DC 、磁化强度均降低。此外，样品在发生金属—绝缘体转变的同时伴随有铁磁—顺磁的转变。
채용전통적고온고상소결법제비료다정양품（La1－x Gdx ）4／3 Sr5／3 Mn2 O7（x ＝0，0．05），이용 XRD 검측료량양품적결구，결과표명：량양품균위 Sr3 Ti2 O7형사방결구，공간군위 I4／mmm，통과물성측량계통（PPMS）화초도양자자강계（SQUID）측량료양품적자성（M－T）이급전성（ρ－T），결과발현：량양품재저온구존재장정적철자태；당 Gd 참입후，유우인기료결구적기변，삭약료쌍교환작용，치사양품（La1－x Gdx ）4／3 Sr5／3 Mn2 O7（x ＝0．05）적삼유（3D）자유서전변온도 T3DC 、자화강도균강저。차외，양품재발생금속—절연체전변적동시반수유철자—순자적전변。
(La1 -x Gdx )4 /3 Sr5 /3 Mn2 O7 (x =0,0.05)polycrystalline samples were prepared by solid state meth-od.The sample’s magnetic and transport properties were studied by using XRD,PPMS and SQUID.The results showed that the sample are Sr3 Ti2 O7 type structure,and space group are I4 /mmm.The samples exist long -range ferromagnetic state in low temperature area.Structure is distorted after Gd3 + doped,which weakened the FMinter-action,decrease TC and magnetization.In addition,metal insulation shift and change of the ferromagnetic paramag-netic occurred at the same time.