Topological phase diagram of mercury cadmium telluride quantum wells

We present a systematic experimental study of the topological phase transition in a series of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mo>∼</a:mo><a:mn>10</a:mn><a:mspace width="0.16em"/><a:mi>nm</a:mi></a:mrow></a:math> thick <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:mrow><c:msub><c:mi>Hg</c:mi><c:mrow><c:mn>1</c:mn><c:mo>−</c:mo><c:mi>x</c:mi></c:mrow></c:msub><c:msub><c:mi>Cd</c:mi><c:mi>x</c:mi></c:msub><c:mi>Te</c:mi></c:mrow></c:math> quantum wells by tuning the Cd content <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mi>x</d:mi></d:math>. We provide detailed structural and magneto-optical spectroscopic characterization measurements and establish a comprehensive picture of the alloy structural and energetic properties. Using these as input, we employ <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"><e:mrow><e:mtext mathvariant="bold">k</e:mtext><e:mo>·</e:mo><e:mtext mathvariant="bold">p</e:mtext></e:mrow></e:math> modeling to establish the topological phase diagram of <h:math xmlns:h="http://www.w3.org/1998/Math/MathML"><h:mrow><h:msub><h:mi>Hg</h:mi><h:mrow><h:mn>1</h:mn><h:mo>−</h:mo><h:mi>x</h:mi></h:mrow></h:msub><h:msub><h:mi>Cd</h:mi><h:mi>x</h:mi></h:msub><h:mi>Te</h:mi></h:mrow></h:math> in dependence on the Cd content and quantum well thickness for thin films which are pseudomorphically strained to the lattice constant of pure CdTe.