I have created Search Service Application Topology for sharepoint 2013 using below powershell Script

# Create a new Search Service Application in SharePoint 2013

 Add-PSSnapin Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue

# Settings

$IndexLocation = "E:\Sharepoint 2013Index” #Location must be empty, will be deleted during the process!
$SearchAppPoolName = "SearchServiceApplicationPool
$SearchAppPoolAccountName = "ramu\spsearchapp”
$SearchServerName = (Get-ChildItem env:computername).value
$SearchServiceName = "Search Service Application"
$SearchServiceProxyName = "Search Service Application Proxy"
$DatabaseName = "Search Service AdminDB"

Write-Host -ForegroundColor Yellow "Checking if Search Application Pool exists"

$SPAppPool = Get-SPServiceApplicationPool -Identity $SearchAppPoolName -ErrorAction SilentlyContinue

if (!$SPAppPool)
{
    Write-Host -ForegroundColor Green "Creating Search Application Pool"
    $spAppPool = New-SPServiceApplicationPool -Name $SearchAppPoolName -Account $SearchAppPoolAccountName -Verbose
}

# Start Services search service instance

Write-host "Start Search Service instances...."

Start-SPEnterpriseSearchServiceInstance $SearchServerName -ErrorAction SilentlyContinue
Start-SPEnterpriseSearchQueryAndSiteSettingsServiceInstance $SearchServerName -ErrorAction SilentlyContinue
 
Write-Host -ForegroundColor Yellow "Checking if Search Service Application exists"

$ServiceApplication = Get-SPEnterpriseSearchServiceApplication -Identity $SearchServiceName -ErrorAction SilentlyContinue

if (!$ServiceApplication)
{
Write-Host -ForegroundColor Green "Creating Search Service Application"
$ServiceApplication = New-SPEnterpriseSearchServiceApplication -Partitioned -Name $SearchServiceName -ApplicationPool $spAppPool.Name -DatabaseName $DatabaseName
}
 
Write-Host -ForegroundColor Yellow "Checking if Search Service Application Proxy exists"

$Proxy = Get-SPEnterpriseSearchServiceApplicationProxy -Identity $SearchServiceProxyName -ErrorAction SilentlyContinue

if (!$Proxy)
{
  Write-Host -ForegroundColor Green "Creating Search Service Application Proxy"
  New-SPEnterpriseSearchServiceApplicationProxy -Partitioned -Name $SearchServiceProxyName -SearchApplication        $ServiceApplication
}

$ServiceApplication.ActiveTopology

Write-Host $ServiceApplication.ActiveTopology

# Clone the default Topology (which is empty) and create a new one and then activate it

Write-Host "Configuring Search Component Topology...."

$clone = $ServiceApplication.ActiveTopology.Clone()
$SSI = Get-SPEnterpriseSearchServiceInstance -local

New-SPEnterpriseSearchAdminComponent –SearchTopology $clone -SearchServiceInstance $SSI
New-SPEnterpriseSearchContentProcessingComponent –SearchTopology $clone -SearchServiceInstance $SSI
New-SPEnterpriseSearchAnalyticsProcessingComponent –SearchTopology $clone -SearchServiceInstance $SSI
New-SPEnterpriseSearchCrawlComponent –SearchTopology $clone -SearchServiceInstance $SSI

Remove-Item -Recurse -Force -LiteralPath $IndexLocation -ErrorAction SilentlyContinue

mkdir -Path $IndexLocation -Force
New-SPEnterpriseSearchIndexComponent –SearchTopology $clone -SearchServiceInstance $SSI -RootDirectory $IndexLocation
New-SPEnterpriseSearchQueryProcessingComponent –SearchTopology $clone -SearchServiceInstance $SSI
$clone.Activate()

Write-host "Your search service application $SearchServiceName is now ready"