Symmetric Pöschl-Teller potential: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle -{\frac {\lambda (\lambda +1)}{2}}\operatorname {sech} ^{2}(x)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mo>−<!-- − --></mo><mrow class="MJX-TeXAtom-ORD"><mfrac><mrow><mi>λ<!-- λ --></mi><mo stretchy="false">(</mo><mi>λ<!-- λ --></mi><mo>+</mo><mn>1</mn><mo stretchy="false">)</mo></mrow><mn>2</mn></mfrac></mrow><msup><mi>sech</mi><mrow class="MJX-TeXAtom-ORD"><mn>2</mn></mrow></msup><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle -{\frac {\lambda (\lambda +1)}{2}}\operatorname {sech} ^{2}(x)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/00aa4ed1d301891216f3ef189395d3288190218d" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -1.838ex; width:20.021ex; height:5.676ex;" alt="{\displaystyle -{\frac {\lambda (\lambda +1)}{2}}\operatorname {sech} ^{2}(x)}"></span>. It shows the eigenvalues for μ=1, 2, 3, 4, 5, 6.
<a href="//commons.wikimedia.org/wiki/User:Nicoguaro" title="User:Nicoguaro">Nicoguaro</a>
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<span class="int-own-work" lang="en">Own work</span>