Synthesis And Physical Properties Study Of The Antiperovskite Mn₃Cu_1-xZn_xN

Although the structure of antiperovskite compounds is analogical to that of theperovskite oxide,its properties are little known due to the absence of research. Inrecent years, several novel phenomenon in anperovskite have been found, such asnegative thermal expansion （NTE）, piezomagnetism, magnetocaloric,magetoresistance and near-zero temperature coefficient of resistance （TCR）. Thisdissertation aims at the synthesis and investigation on the physical properties ofantiperovskite Mn₃Cu_1-xZn_xN. It is expected to accumulate data and deepen theunderstanding of this material system and also be helpful to related material design.In addition, this dissertation also offers a new rout for rapidly synthesis of thismaterial.According to the experimental results, the magnetic and electrical transportproperty of Mn₃Cu_1-xZn_xN can be tuned by changing the ratio of doping element. Asfor Mn₃Cu_0.1Zn_0.9N, Cu doping induces ferrimagnetism and weakensantiferromagnetism, and a plateau-like feature can be seen in ρ（T） curve ofMn₃Cu_0.1Zn_0.9N. In addition, in Mn₃Cu_0.5Zn_0.5N we found the temperature assistantmagnetoresistance switch effect, which is correlated with its intrinsic magnetictransition （antiferromagntism–ferrimagnetism-paramagnetism）, according topreminary analysis, this effet may originate from the competition between magneticand lattice scattering. Studies on the other components in Mn₃CuxZn1-xN show atransition from ferrimagnetism to antiferromagnetism can be induced by changingthe ratio between doping elements. The critical behavior at the paramagnetic （PM）to ferromagnetic （FM） transition in Mn₃CuN is investigated. It is found that criticalbehavior in Mn₃CuN is divided into two independent stages: i) ZI（T> T_c）,mean-field model is assumed to occupy a predominate position. ii) ZII（T <T_c）critical behavior can be seen as the competition between Heisenberg model andmean-field model. We explore microwave route to synthesis antiperovskite compounds,which has several advantages such as high efficiency, low cost and pure product comparedwith the traditional method.