Figure 1

(Color online) (a) Configuration of $d$ electrons at each ion. [(b)–(d)] Schematic pictures of the electronic state of $\mathrm{Sr}\mathrm{Ti}{\mathrm{O}}_3$ with V or Cr as impurities.Reuse & Permissions

Figure 2

(Color online) Upper panel: Temperature dependence of magnetic susceptibility of (a) ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{Cr}}_x{\mathrm{O}}_3$ and (b) ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{V}}_x{\mathrm{O}}_3$ with fixed Cr or V concentration, $x=0.2$, and various nominal concentrations of itinerant carriers $\left({\mathrm{Ti}}^{3+}\right)$ $y$. The inset in (a) shows the magnetic-field dependence of magnetization for $y=0.2$. The dashed line in (b) is the data for $y=0.2$ without V or Cr. Lower panel: Temperature dependence of electrical resistivity of (c) ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{Cr}}_x{\mathrm{O}}_3$ and (b) ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{V}}_x{\mathrm{O}}_3$ with fixed $x$ (number of Cr or V) and various values of $y$ (number of ${\mathrm{Ti}}^{3+}$). The dashed lines in (c) and (d) are the data without V or Cr.Reuse & Permissions

Figure 3

(Color online) (a) Hall resistivity vs magnetic field for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{V}}_x{\mathrm{O}}_3$ with $y=0.1$ (number of ${\mathrm{Ti}}^{3+}$) and $x=0,0.2$ (number of V). (b) Carrier concentration $n_c$ estimated from Hall coefficient as a function of $y$ (number of ${\mathrm{Ti}}^{3+}$) for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}\mathrm{V}\left(\mathrm{Cr}\right){\mathrm{O}}_3$ without V or Cr (open circles), with V ($x=0.2$, closed circles), and with Cr (crosses). [(c)–(e)] Optical reflectivity spectra at room temperature for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{V}}_x{\mathrm{O}}_3$ with $x=0$ and 0.2 (number of V) and various values of $y$ (number of ${\mathrm{Ti}}^{3+}$). The insets show the optical conductivity spectrum of each sample. (f) Effective number of electrons $\left(N_{\mathrm{eff}}\right)$ as a function of $y$ (number of ${\mathrm{Ti}}^{3+}$) for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{V}}_x{\mathrm{O}}_3$ with $x=0$ and 0.2 (number of V). (g) Effective mass $m^{*}$ normalized to that of free electrons $m_0$, estimated from $N_{\mathrm{eff}}$ and $n_c$, as a function of $y$ (number of ${\mathrm{Ti}}^{3+}$) for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{V}}_x{\mathrm{O}}_3$.Reuse & Permissions

Figure 4

(Color online) (a) Hall resistivity vs magnetic field for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{Cr}}_x{\mathrm{O}}_3$ with $x=0.15$ (number of Cr) and $y=0.1$ (number of ${\mathrm{Ti}}^{3+}$). (b) Temperature dependence of the normal term $R_H$ (closed symbols, left axis) and the anomalous term $R_s$ (open symbols, right axis) of Hall resistivity for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{Cr}}_x{\mathrm{O}}_3$ with $y=0.1$ (number of ${\mathrm{Ti}}^{3+}$) and various values of $x$ (number of Cr). [(c) and (d)] Temperature dependence of mobility and resistivity for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{Cr}}_x{\mathrm{O}}_3$ with $y=0.1$ (number of ${\mathrm{Ti}}^{3+}$) and various values of $x$ (number of Cr). (e) The anomalous term $\left(R_s\right)$ vs the ordinary term $\left(R_H\right)$ of Hall resistivity for ${\mathrm{Sr}}_{1-x-y}{\mathrm{La}}_{x+y}{\mathrm{Ti}}_{1-x}{\mathrm{Cr}}_x{\mathrm{O}}_3$ with various values of $(x,y)$.Reuse & Permissions